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  • 101. Boström, Jonas
    et al.
    Aquilante, Francesco
    Pedersen, Thomas Bondo
    Lindh, Roland
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Analytical gradients of Hartree-Fock exchange with density fitting approximations2013In: Journal of Chemical Theory and Computation, ISSN 1549-9618, E-ISSN 1549-9626, Vol. 9, no 1, p. 204-212Article in journal (Refereed)
    Abstract [en]

    We extend the local exchange (LK) algorithm [Aquilante, F.; Pedersen, T. B.; Lindh, R. J. Chem. Phys.2007, 126, 194106] to the calculation of analytical gradients with density fitting. We discuss the features of the screening procedure and demonstrate the possible advantages of using this formulation, which is easily interfaced to a standard integral-direct gradient code. With auxiliary basis sets obtained from Cholesky decomposition of atomic or molecular integral blocks with a decomposition threshold of 10-4Eh, typical errors due to the density fitting in bond lengths, bond angles, and dihedral angles are 0.1 pm, 0.1°, and 0.5°, respectively. The overall speedup of geometry optimizations is about 1 order of magnitude for atomic natural-orbital-type basis sets but much less pronounced for correlation-consistent basis sets.

  • 102. Boström, Jonas
    et al.
    Veryazov, Valera
    Aquilante, Francesco
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Bondo Pedersen, Thomas
    Lindh, Roland
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Analytical gradients of the second-order Møller–Plesset energy using Cholesky decompositions2014In: International Journal of Quantum Chemistry, ISSN 0020-7608, E-ISSN 1097-461X, Vol. 114, no 5, p. 321-327Article in journal (Refereed)
    Abstract [en]

    An algorithm for computing analytical gradients of the second-order Møller–Plesset (MP2) energy using density fitting (DF) is presented. The algorithm assumes that the underlying canonical Hartree–Fock reference is obtained with the same auxiliary basis set, which we obtain by Cholesky decomposition (CD) of atomic electron repulsion integrals. CD is also used for the negative semidefinite MP2 amplitude matrix. Test calculations on the weakly interacting dimers of the S22 test set (Jurečka et al., Phys. Chem. Chem. Phys. 2006, 8, 1985) show that the geometry errors due to the auxiliary basis set are negligible. With double-zeta basis sets, the error due to the DF approximation in intermolecular bond lengths is better than 0.1 pm. The computational time is typically reduced by a factor of 6–7.

  • 103. Bouchet, Aude
    et al.
    Brotin, Thierry
    Linares, Mathieu
    KTH, School of Biotechnology (BIO), Theoretical Chemistry (closed 20110512).
    Ågren, Hans
    KTH, School of Biotechnology (BIO), Theoretical Chemistry (closed 20110512).
    Cavagnat, Dominique
    Buffeteau, Thierry
    Conformational Effects Induced by Guest Encapsulation in an Enantiopure Water-Soluble Cryptophane2011In: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 76, no 5, p. 1372-1383Article in journal (Refereed)
    Abstract [en]

    A new water-soluble cryptophane 1 derivative (penta-hydroxyl cryptophane-A) has been synthesized from cryptophanol-A and the chiroptical properties of its two enantiomers M M-1 and P P-1 have been studied by polarimetry, electronic circular dichroism (ECD), and vibrational circular dichroism (VCD). Cryptophane 1 shows specific circular dichroism responses upon complexation that depend on the size of the guest and on the nature of the counterion (Li+, Na+, K+, Cs+) present in the solution. In LiOH and NaOH solutions, chiroptical changes induced by the encapsulation of guests and by the presence of cations in the vicinity of hosts can be interpreted from molecular dynamics (MD) and ab initio calculations by subtle conformational changes of the bridges. In KOH solution, the exchange dynamics is dependent on the size of the guest molecules, whereas in CsOH solution no encapsulation effect is observed whatever the size of the guest molecule. This last behavior comes from the fact that host 1 exhibits a very high affinity for cesium cations.

  • 104.
    Boudjemia, Nacer
    et al.
    Univ Oulu, Nano & Mol Syst Res Unit, POB 3000, Oulu 90014, Finland.
    Jankala, Kari
    Univ Oulu, Nano & Mol Syst Res Unit, POB 3000, Oulu 90014, Finland.
    Gejo, Tatsuo
    RIKEN, SPring 8 Ctr, 1-1-1 Kouto, Sayo, Hyogo 6795148, Japan;Univ Hyogo, Grad Sch Mat Sci, Kamigori, Hyogo 6781297, Japan.
    Nagaya, Kiyonobu
    RIKEN, SPring 8 Ctr, 1-1-1 Kouto, Sayo, Hyogo 6795148, Japan;Kyoto Univ, Dept Phys, Kyoto 6068502, Japan.
    Tamasaku, Kenji
    RIKEN, SPring 8 Ctr, 1-1-1 Kouto, Sayo, Hyogo 6795148, Japan.
    Huttula, Marko
    Univ Oulu, Nano & Mol Syst Res Unit, POB 3000, Oulu 90014, Finland.
    Piancastelli, Maria Novella
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics. RIKEN, SPring 8 Ctr, 1-1-1 Kouto, Sayo, Hyogo 6795148, Japan;Sorbonne Univ, CNRS, LCPMR, F-75005 Paris, France.
    Simon, Marc
    RIKEN, SPring 8 Ctr, 1-1-1 Kouto, Sayo, Hyogo 6795148, Japan;Sorbonne Univ, CNRS, LCPMR, F-75005 Paris, France.
    Oura, Masaki
    RIKEN, SPring 8 Ctr, 1-1-1 Kouto, Sayo, Hyogo 6795148, Japan.
    Deep core photoionization of iodine in CH3I and CF3I molecules: how deep down does the chemical shift reach?2019In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 21, no 10, p. 5448-5454Article in journal (Refereed)
    Abstract [en]

    Hard X-ray electron spectroscopic study of iodine 1s and 2s photoionization of iodomethane (CH3I) and trifluoroiodomethane (CF3I) molecules is presented. The experiment was carried out at the SPring-8 synchrotron radiation facility in Japan. The results are analyzed with the aid of relativistic molecular and atomic calculations. It is shown that charge redistribution within the molecule is experimentally observable even for very deep levels and is a function of the number of electron vacancies. We also show that the analysis of Auger spectra subsequent to hard X-ray photoionization can be used to provide insight into charge distribution in molecules and highlight the necessity of quantum electrodynamics corrections in the prediction of core shell binding energies in molecules that contain heavy atoms.

  • 105.
    Boukharta, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Computational and Systems Biology.
    Computational Modelling of Ligand Complexes with G-Protein Coupled Receptors, Ion Channels and Enzymes2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Accurate predictions of binding free energies from computer simulations are an invaluable resource for understanding biochemical processes and drug action. The primary aim of the work described in the thesis was to predict and understand ligand binding to several proteins of major pharmaceutical importance using computational methods.

    We report a computational strategy to quantitatively predict the effects of alanine scanning and ligand modifications based on molecular dynamics free energy simulations. A smooth stepwise scheme for free energy perturbation calculations is derived and applied to a series of thirteen alanine mutations of the human neuropeptide Y1 G-protein coupled receptor and a series of eight analogous antagonists. The robustness and accuracy of the method enables univocal interpretation of existing mutagenesis and binding data. We show how these calculations can be used to validate structural models and demonstrate their ability to discriminate against suboptimal ones. Site-directed mutagenesis, homology modelling and docking were further used to characterize agonist binding to the human neuropeptide Y2 receptor, which is important in feeding behavior and an obesity drug target.  In a separate project, homology modelling was also used for rationalization of mutagenesis data for an integron integrase involved in antibiotic resistance.

    Blockade of the hERG potassium channel by various drug-like compounds, potentially causing serious cardiac side effects, is a major problem in drug development. We have used a homology model of hERG to conduct molecular docking experiments with a series of channel blockers, followed by molecular dynamics simulations of the complexes and evaluation of binding free energies with the linear interaction energy method. The calculations are in good agreement with experimental binding affinities and allow for a rationalization of three-dimensional structure-activity relationships with implications for design of new compounds. Docking, scoring, molecular dynamics, and the linear interaction energy method were also used to predict binding modes and affinities for a large set of inhibitors to HIV-1 reverse transcriptase. Good agreement with experiment was found and the work provides a validation of the methodology as a powerful tool in structure-based drug design. It is also easily scalable for higher throughput of compounds.

  • 106. Brandt, Peter
    et al.
    Norrby, Per-Ola
    Daly, Adrian M
    Gilheany, Declan G
    Chromium-salen-mediated alkene epoxidation: a theoretical and experimental study indicates the importance of spin-surface crossing and the presence of a discrete intermediate.2002In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 8, no 18, p. 4299-307Article in journal (Refereed)
    Abstract [en]

    The mechanism of alkene epoxidation by chromium(v) oxo salen complexes has been studied by DFT and experimental methods. The reaction is compared to the closely related Mn-catalyzed process in an attempt to understand the dramatic difference in selectivity between the two systems. Overall, the studies show that the reactions have many similarities, but also a few critical differences. In agreement with experiment, the chromium system requires a change from low- to high-spin in the catalytic cycle, whereas the manganese system can proceed either with spin inversion or entirely on the high-spin surface. The low-spin addition of metal oxo species to an alkene leads to an intermediate which forms epoxide either with a barrier on the low-spin surface or without a barrier after spin inversion. Supporting evidence for this intermediate was obtained by using vinylcyclopropane traps. The chromium(v) oxo complexes can adopt a stepped shape or form a more concave surface, analogous to previous results on manganese salen complexes.

  • 107.
    Brena, Barbara
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    First principles modeling of soft X-ray spectroscopy of complex systems2005Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    The electronic structures of complex systems have been studied by theoretical calculations of soft x-ray spectroscopies like x-ray photoelectron spectroscopy, near edge x-ray absorption fine structure, and x-ray emission spectroscopies. A new approach based on time dependent density functional theory has been developed for the calculation of shake-up satellites associated with photoelectron spectra. This method has been applied to the phthalocyanine molecule, describing in detail its electronic structure, and revealing the origin of controversial experimental features. It is illustrated in this thesis that the theoretical intepretation plays a fundamental role in the full understanding of experimental spectra of large and complex molecular systems. Soft x-ray spectroscopies and valence band photoelectron spectroscopies have proved to be powerful tools for isomer identification, in the study of newly synthesized fullerene molecules, the azafullerene C48N12 and the C50Cl10 molecule, as well as for the determination of the conformational changes in the polymeric chain of poly(ethylene oxide). The dynamics of the core excitation process, revealed by the vibrational fine structure of the absorption resonances, has been studied by means of density functional and transition state theory approaches.

  • 108.
    Brena, Barbara
    et al.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Carniato, S.
    Luo, Yi
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Functional and basis set dependence of K-edge shake-up spectra of molecules2005In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 122, no 18, p. 184316-Article in journal (Refereed)
    Abstract [en]

    A straightforward approach for computing the K -edge shake-up spectra of molecules based on equivalent core-hole linear response theory at both Hartree-Fock and density functional theory levels is proposed. Benchmark calculations have been performed to explore its sensitivity to different types of functionals and basis sets for the carbon 1s shake-up spectra of benzene and metal-free phthalocyanine (H2 Pc). A very good agreement with previous theoretical and experimental works for the benzene molecule has been obtained for all the functionals and basis sets tested. Electron correlation is found to be essential for a good description of the H2 Pc system, whose experimental C 1s shake-up spectrum is best reproduced by the hybrid density functional.

  • 109.
    Brena, Barbara
    et al.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Carniato, Stéphane
    Luo, Yi
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Electronic and geometrical structures of the N1s-13(pi) excited states in the N2O moleculeManuscript (preprint) (Other academic)
  • 110.
    Brena, Barbara
    et al.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Luo, Yi
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Characterization of the electronic structure of C50Cl10 by means of soft x-ray spectroscopies2005In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 123, no 24, p. 244305-1-244305-4Article in journal (Refereed)
    Abstract [en]

    The electronic structure of the last synthesized fullerene molecule, the C50Cl10, has been characterized by theoretical simulation of x-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, and near-edge x-ray-absorption fine structure. All the calculations were performed at the gradient-corrected and hybrid density-functional theory levels. The combination of these techniques provides detailed information about the valence band and the unoccupied molecular orbitals, as well as about the carbon core orbitals.

  • 111.
    Brena, Barbara
    et al.
    KTH, Superseded Departments, Biotechnology.
    Luo, Yi
    KTH, Superseded Departments, Biotechnology.
    Electronic structures of azafullerene C48N122003In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 119, no 14, p. 7139-7144Article in journal (Refereed)
    Abstract [en]

    Two recently proposed low-energy azafullerene C48N12 isomers have been theoretically characterized using x-ray spectroscopies. The x-ray photoelectron spectroscopy, the near-edge absorption fine structure, the x-ray emission spectroscopy, and the ultraviolet photoelectron spectroscopy for both isomers have been predicted at the gradient-corrected density functional theory level. These spectroscopies together give a comprehensive insight of the electronic structure on the core, valence, and unoccupied orbitals. They have also provided a convincing way for identifying the isomer structures.

  • 112.
    Brena, Barbara
    et al.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry (closed 20110512).
    Luo, Yi
    KTH, School of Biotechnology (BIO), Theoretical Chemistry (closed 20110512).
    Time-dependent DFT calculations of core electron shake-up states of metal-(free)-phthalocyanines2006In: Radiation Physics and Chemistry, ISSN 0969-806X, E-ISSN 1879-0895, Vol. 75, no 11, p. 1578-1581Article in journal (Refereed)
    Abstract [en]

    We have introduced a new approach for the calculation of the shake-up structures of molecular photoelectron spectra, based on the combination of time-dependent density functional theory (TD-DFT) and equivalent core hole (or Z + 1) approximation. The method, suitable for large molecules, has been applied to compute the complex shake-up states associated with the carbon Is X-ray photoelectron spectroscopy (XPS) of metal-free and nickel phthalocyanines (H2Pc and NiPc, respectively). A similar satellite profile emerges for both molecules.

  • 113.
    Brena, Barbara
    et al.
    KTH, Superseded Departments, Biotechnology.
    Luo, Yi
    KTH, Superseded Departments, Biotechnology.
    Nyberg, Mats
    KTH, Superseded Departments, Biotechnology.
    Puglia, C.
    et al.,
    Equivalent core-hole time-dependent density functional theory calculations of carbon 1s shake-up states of phthalocyanine2004In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 70, no 19, p. 195214-Article in journal (Refereed)
    Abstract [en]

    The shake-up transition energies of the carbon 1s photoelectron spectrum of metal-free phthalocyanine (H2Pc) have been calculated by means of time-dependent density functional theory, for which an equivalent core approximation is adopted. Model calculations for the C 1s shake-up states of benzene are in excellent agreement with the latest experimental results. The complex C 1s shake-up structures associated with the aromatic and pyrrole carbons in the phthalocyanine are computed, as well as their ionization potentials. They allow us to determine the origin of the anomalous intensity ratio between the pyrrole and benzene carbons in a high resolution C 1s photoelectron spectrum measured for a H2Pc film, as due to a benzene-related shake-up contribution, hidden under the pyrrole main intensity feature.

  • 114.
    Brena, Barbara
    et al.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry (closed 20110512).
    Nordlund, D
    Odelius, M
    Ogasawara, H
    Nilsson, A
    Pettersson, L G M
    Ultrafast molecular dissociation of water in ice2004In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 93, no 14, p. 148302-Article in journal (Refereed)
    Abstract [en]

    Using x-ray emission and photoemission spectroscopies to measure the occupied valence levels in a thin crystalline ice film, we resolve the ionization-induced dissociation of water in ice on a femtosecond time scale. Isotope substitution confirms proton transfer during the core-hole lifetime in spite of the nonresonant excitation. Through ab initio molecular dynamics on the core-ionized state, the dissociation and spectrum evolution are followed at femtosecond intervals. The theoretical simulations confirm the experimental analysis and allow for a detailed study of the dissociative reaction path.

  • 115.
    Brena, Barbara
    et al.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Zhuang, G. V.
    Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley.
    Augustsson, A.
    Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley.
    Liu, G.
    Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, Berkeley.
    Nordgren, J.
    Department of Physics, Uppsala University.
    Guo, J. H.
    Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley.
    Ross, P. N.
    Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley.
    Luo, Yi
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Conformation dependence of electronic structures of poly(ethylene oxide)2005In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 109, no 16, p. 7907-7914Article in journal (Refereed)
    Abstract [en]

    The electronic structure of pure poly(ethylene oxide) (PEO) for four different polymeric chain conformations has been studied by Hartree-Fock (HF) and density functional theory (DFT) through the analysis of their valence band photoelectron spectroscopy (VB-PES), X-ray emission spectroscopy (XES), and resonant inelastic X-ray scattering (RIXS). It is shown that the valence band of PEO presents specific conformation dependence, which can be used as a fingerprint of the polymeric structures. The calculated spectra have been compared with experimental results for PEO powder.

  • 116.
    Brinck, Tore
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Carlqvist, Peter
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Halldin Stenlid, Joakim
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Local Electron Attachment Energy and Its Use for Predicting Nucleophilic Reactions and Halogen Bonding2016In: JOURNAL OF PHYSICAL CHEMISTRY A, ISSN 1089-5639, Vol. 120, no 50, p. 10023-10032Article in journal (Refereed)
    Abstract [en]

    A new local property, the local electron attachment energy [E(r)], is introduced and is demonstrated to, be a useful guide to predict intermolecular interactions and chemical reactivity. The E(r) is analogous to the average local ionization energy but indicates susceptibility toward interactions with nucleophiles rather than electrophiles. The functional form E(r) is motivated based on Janak's theorem and the piecewise linear energy dependence of electron addition to atomic and molecular systems. Within the generalized Kohn-Sham method (GKS-DFT), only the virtual orbitals with negative eigenvalues contribute to E(r). In the, present study, E(r) has been computed from orbitals obtained from GKS-DFT computations with a hybrid exchange correlation functional. It is shown that E(r) computed on a molecular isodengty surface, E-S(r), reflects the regioselectivity and relative reactivity for nucleophilic aromatic substitution, nucleophilic addition to activated double bonds, and formation of halogen bonds. Good to excellent correlations between experimental or theoretical measures of interaction strengths and minima in E-S(r) (E-S,E-min) are demonstrated.

  • 117.
    Brinck, Tore
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Nyberg Borrfors, Andre
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry. KTH Royal Inst Technol, CBH, Dept Chem, Appl Phys Chem, SE-10044 Stockholm, Sweden..
    Electrostatics and polarization determine the strength of the halogen bond: a red card for charge transfer2019In: JOURNAL OF MOLECULAR MODELING, Vol. 25, no 5, article id 125Article in journal (Refereed)
    Abstract [en]

    A series of 20 halogen bonded complexes of the types R-Br center dot center dot center dot Br- (R is a substituted methyl group) and R '-CC-Br center dot center dot center dot Br- are investigated at the M06-2X/6-311+G(d,p) level of theory. Computations using a point-charge (PC) model, in which Br- is represented by a point charge in the electronic Hamiltonian, show that the halogen bond energy within this set of complexes is completely described by the interaction energy (E-PC) of the point charge. This is demonstrated by an excellent linear correlation between the quantum chemical interaction energy and E-PC with a slope of 0.88, a zero intercept, and a correlation coefficient of R-2=0.9995. Rigorous separation of E-PC into electrostatics and polarization shows the high importance of polarization for the strength of the halogen bond. Within the data set, the electrostatic interaction energy varies between 4 and-18kcal mol(-1), whereas the polarization energy varies between -4 and-10kcal mol(-1). The electrostatic interaction energy is correlated to the sum of the electron-withdrawing capacities of the substituents. The polarization energy generally decreases with increasing polarizability of the substituents, and polarization is mediated by the covalent bonds. The lower (more favorable) E-PC of CBr4---Br- compared to CF3Br center dot center dot center dot Br- is found to be determined by polarization as the electrostatic contribution is more favorable for CF3Br center dot center dot center dot Br-. The results of this study demonstrate that the halogen bond can be described accurately by electrostatics and polarization without any need to consider charge transfer.

  • 118.
    Brinck, Tore
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Stenlid, Joakim H.
    Stockholm Univ, AlbaNova Univ Ctr, Dept Phys, SE-10691 Stockholm, Sweden..
    The Molecular Surface Property Approach: A Guide to Chemical Interactions in Chemistry, Medicine, and Material Science2019In: ADVANCED THEORY AND SIMULATIONS, ISSN 2513-0390, Vol. 2, no 1, article id 1800149Article in journal (Refereed)
    Abstract [en]

    The current status of the molecular surface property approach (MSPA) and its application for analysis and prediction of intermolecular interactions, including chemical reactivity, are reviewed. The MSPA allows for identification and characterization of all potential interaction sites of a molecule or nanoparticle by the computation of one or more molecular properties on an electronic isodensity surface. A wide range of interactions can be analyzed by three properties, which are well-defined within Kohn-Sham density functional theory. These are the electrostatic potential, the average local ionization energy, and the local electron attachment energy. The latter two do not only reflect the electrostatic contribution to a chemical interaction, but also the contributions from polarization and charge transfer. It is demonstrated that the MSPA has a high predictive capacity for non-covalent interactions, for example, hydrogen and halogen bonding, as well as organic substitution and addition reactions. The latter results open u p applications within drug design and medicinal chemistry. The application of MSPA has recently been extended to nanoparticles and extended surfaces of metals and metal oxides. In particular, nanostructural effects on the catalytic properties of noble metals are rationalized. The potential for using MSPA in rational design of heterogeneous catalysts is discussed.

  • 119.
    Brinne Roos, Johanna
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Electron Recombination with Small Molecular Ions2007Licentiate thesis, comprehensive summary (Other scientific)
    Abstract [en]

    In this thesis I have theoretically studied electron recombination processes with small molecular ions.

    In these kind of processes resonant states are involved. To calculate the potential energy for these states as a function of internuclear distance, structure calculations and scattering calculations have to be performed.

    So far I have been studying the ion-pair formation with in electron recombination with H3+. The cross section for this process has been calculated using different kind of models, both a time dependent quantum mechanical and a semiclassical.

    I have also studied the direct process of dissociative recombination of HF+. To calculate the total cross section for this process, we have performed wave packet propagation on thirty resonant states and summed up the individual cross sections for these states.

    The cross sections for both these processes have a similar appearance to those measured experimentally in the ion storage ring CRYRING in Stockholm.

  • 120.
    Br�ndas, Erkki
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Chemistry, Department of Physical and Analytical Chemistry, Quantum Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical and Analytical Chemistry. kvantkemi.
    Sabin, John R.
    Advances in Quantum Chemistry: Theory of the Interaction of Radiation with Biomolecules2007In: Advances in Quantum Chemistry: Preface, ISSN 0065-3276, Vol. 52, p. xi-xiiArticle, review/survey (Other (popular scientific, debate etc.))
    Abstract [en]

    This thematic issue of Advances in Quantum Chemistry is devoted to the theory of the interaction of radiation with biological systems. The subject is timely, as knowledge of the fundamental physics and chemistry of the interaction is critical to understanding problems as critical as radiation therapy of tumors and radiation protection in space. A true understanding of the interaction of radiation with a biological entity requires study of phenomena ranging over many orders of magnitude in size and time. In this volume, however, we concentrate on the individual collision processes between an ion or photon and a single biomolecule. The volume is composed of thirteen contributions from specialists in the field.

    As most of the theory used in this volume is based in quantum mechanics, the size of target systems under consideration is generally small: There are calculations on nucleobases, on DNA radicals, on transient negative ions (TNI), and on the most common biomolecule - water. All are important for the understanding of the primary ion-biomolecule interactions. However, the volume does not go to larger clusters such as double strands, nor to longer timescales where the chemical phase of radiation damage becomes important.

    It is very easy for a theorist to carry out complex calculations on a system thought to be both interesting and relevant to the biological problem, only to discover at some later time that the interest remains but that these is no biological relevance to the problem. To put this problem in perspective, the first paper, after a short introduction, is by an experimentalist, Clemens von Sonntag who discusses the calculation of ion-molecule reactive collisions with particular emphasis on the types of problems where quantum calculations on biomolecules would be of use to experimentalists.

    Von Sonntag�s paper is followed by a series of contributions describing various aspects of radiation damage.

    The first a contribution by Mu�oz et al. concerning high accuracy quantum mechanical modeling of energy deposition by electrons in biologically important molecules. These calculations are used to determine parameters used as input to a Monte Carlo scheme to simulate energy deposition.

    Radicals, and their importance to radiobiological processes are the subject of the next two papers. Li and Sevilla discuss electrons and holes produced in DNA models by ionizing radiation and the effect of these radicals on the subsequent chemical reactions of the biomolecules, while Tur_ek addresses structures and energetics of nucleobase and carbohydrate radical reactions using density functional methods.

    The next contribution, authored by Stolterfoht et al., treats one of the most ubiquitous processes in radiation damage studies: Namely electron capture and fragmentation of water by swift ions. High levels of dynamical theory are used to calculate appropriate cross sections, which are compared to experimental results.

    As much of the radiation damage in biological systems arises from secondary, or delta, electrons coming from ionization of water by the incoming radiation, the interaction of these electrons with biological molecules is of utmost importance in the overall understanding of radiation damage. In the next paper, Jack Simons uses high level quantum mechanical theory to discuss the formation of a transient negative ion (TNI) in a DNA fragment and the mechanism that leads to a subsequent strand break. This paper is followed by a contribution by Baccarelli et al., which also deals with TNI�s, but in this case, their formation from biological molecules in the gas phase. Continuing with the theme of electron attachment to biomolecules, Jalbout and Adamowicz present ab initio quantum mechanical studies of electron attachment to DNA base complexes. Following that paper, Sulik and T_k�si address the problem of the Fermi shuttle acceleration of secondary electrons using classical trajectory Monte Carlo methods.

    The last two contributions in this volume with energy deposition or stopping power. Akar et al. discuss the stopping power of electrons by biological molecules, while Paul et al. consider the effects of stopping power on dosimetry.

    All in all, we find this an informative and useful collection of papers, and we hope that you enjoy reading it as much as we enjoyed putting it together. Finally, we wish to thank all the authors for their help in producing this volume.

    Erkki Br�ndas and John R. Sabin

    Editors

  • 121.
    Broqvist, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Multiscale modelling: the spiral staircase from theory to experiment2017Conference paper (Other academic)
    Abstract [en]

    Multiscale modelling has become a catch phrase in modern e-science, and is widely (and rather broadly) used in many different research fields. From Wikipedia, one can read the following definition of the phrase:

    In engineering, mathematics, physics, chemistry, bioinformatics, computational biology, meteorology and computer science, multiscale modelling or multiscale mathematics is the field of solving problems which have important features at multiple scales of time and/or space.”

    The materials science community often deals with just such multiscale problems, i.e. problems that at the same time concern macroscale properties such as hardness, colour and ductility, which in turn heavily relies on the microscale (electrons and atoms). In this community, multiscale modelling is often referred to as a solution to bridge existing gaps between “first-principles” theoretical approaches and experiments. The strategy, or aim, of multiscale materials modelling is to connect data from different distinguishable levels of models, either in a sequential or a concurrent manner. Generally, these levels are i) quantum mechanical models, which concern electrons, ii) molecular dynamics models, which concern the movement of atoms and molecules, iii) coarse graining models, which concerns groups of atoms/molecules, iv) continuum models, and finally, v) the level of device modelling. Each of these levels is capable of describing a certain time- and length scale, and multiscale materials modelling is thereby often visualized schematically in the form of a “multiscale ladder” or a “multiscale staircase”.

    One of the key obstacles in multiscale materials modelling is to link and harmonize the different models. In some cases, the link between different levels of models can be obvious and made using empirical approaches. Here, constitutive relations, often based on very simplistic ideas such as linearization, or symmetry, plays an important role. However, extending these simple empirical approaches to be used for more complex systems, where discrete and finite size effects are of importance, has been proven difficult.

    In this talk, I will present and discuss common methods used in materials chemistry to link the various levels of models. Both simple (linearized) models and more complex multi-dimensional approaches will be discussed, as well as how this emerging field opens up new opportunities for research collaboration with other disciplines, such as computer science.

  • 122.
    Brumboiu, Iulia Emilia
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    The Electronic Structure of Organic Molecular Materials: Theoretical and Spectroscopic Investigations2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the present thesis the electronic properties of two organic molecules were studied by means of density functional theory (DFT) in connection to their possible applications in organic photovoltaics and molecular spintronics respectively.

    The first analysed system is the C60 derivative PCBM extensively used in polymer solar cells for the charge separation process. Since fullerenes have been shown to undergo modifications as a result of light exposure, investigating their electronic structure is the first step in elucidating the photodegradation process. The electronic excitations from core levels to unoccupied molecular orbitals reveal not only the empty level structure of the molecule, but provide additional information related to the chemical bonds involving a specific atom type. In this way, they represent a means of determining the chemical changes that the molecule might withstand. The electronic transitions from carbon 1s core levels to unoccupied states are explained for the unmodified PCBM by a joint theoretical (DFT) and experimental study using the near edge x-ray absorption fine structure (NEXAFS) spectroscopy.

    The second investigated system is the transition metal phthalocyanine with a manganese atom as the metal center. Manganese phthalocyanine (MnPc) is a single molecular magnet in which the spin switch process can be triggered by various methods. It has been shown, for instance, that the adsorption of hydrogen to the Mn center changes the spin state of the molecule from 3/2 to 1. More interestingly, the process is reversible and can be controlled, opening up the possibility of using MnPc as a quantum bit in magnetic memory devices. Up to this date, the d orbital occupation in MnPc has been under a long debate, both theoretical and experimental studies revealing different configurations. In this thesis the electronic structure of the phthalocyanine is thoroughly analysed by means of DFT and the calculated results are compared to photoelectron spectroscopy measurements. The combination of theoretical and experimental tools reveals that in gas phase at high temepratures the molecule exhibits a mixed electronic configuration. In this light, the possible control of the specific electronic state of the central metal represents an interesting prospect for molecular spintronics.

  • 123.
    Brumboiu, Iulia Emilia
    et al.
    KTH Royal Inst Technol, Dept Theoret Chem & Biol, S-10691 Stockholm, Sweden;Korea Adv Inst Sci & Technol, Dept Chem, Daejeon 34141, South Korea.
    Eriksson, Olle
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Norman, Patrick
    KTH Royal Inst Technol, Dept Theoret Chem & Biol, S-10691 Stockholm, Sweden.
    Atomic photoionization cross sections beyond the electric dipole approximation2019In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 150, no 4, article id 044306Article in journal (Refereed)
    Abstract [en]

    A methodology is developed to compute photoionization cross sections beyond the electric dipole approximation from response theory, using Gaussian type orbitals and plane waves for the initial and final states, respectively. The methodology is applied to compute photoionization cross sections of atoms and ions from the first four rows of the periodic table. Analyzing the error due to the plane wave description of the photoelectron, we find kinetic energy and concomitant photon energy thresholds above which the plane wave approximation becomes applicable. The correction introduced by going beyond the electric dipole approximation increases with photon energy and depends on the spatial extension of the initial state. In general, the corrections are below 10% for most elements, at a photon energy reaching up to 12 keV.

  • 124.
    Brumboiu, Iulia Emilia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory. KTH Royal Inst Technol, Dept Theoret Chem & Biol, S-10691 Stockholm, Sweden; Korea Adv Inst Sci & Technol, Dept Chem, Daejeon 34141, South Korea.
    Haldar, Soumyajyoti
    Lüder, Johann
    Eriksson, Olle
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Herper, Heike C.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Brena, Barbara
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Sanyal, Biplab
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Ligand effects on the linear response Hubbard U: The case of transition metal phthalocyanines2019In: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 123, no 14, p. 3214-3222Article in journal (Refereed)
    Abstract [en]

    It is established that density functional theory (DFT) + U is a better choice compared to DFT for describing the correlated electron metal center in organometallics. The value of the Hubbard U parameter may be determined from linear response, either by considering the response of the metal site alone or by additionally considering the response of other sites in the compound. We analyze here in detail the influence of ligand shells of increasing size on the U parameter calculated from the linear response for five transition metal phthalocyanines. We show that the calculated multiple-site U is larger than the single-site U by as much as 1 eV and the ligand atoms that are mainly responsible for this difference are the isoindole nitrogen atoms directly bonded to the central metal atom. This suggests that a different U value may be required for computations of chemisorbed molecules compared to physisorbed and gas-phase cases.

  • 125.
    Brändas, E., and Goscinski O.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. QUANTUM CHEMISTRY.
    Preface: New Perspectives in Quantum Systems in Chemistry and Physics2001In: Advances in Quantum Chemistry, Vol. 39 and 40, p. xxv-xxviOther (Other scientific)
  • 126.
    Brändas, Erkki
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    A Simple Communication Hypothesis: The Process of Evolution Reconsidered2018In: Progress in Theoretical Chemistry and Physics, ISSN 1567-7354, Vol. 31, p. 381-404Article, review/survey (Refereed)
    Abstract [en]

    The scientific basis of Darwinian evolution is reconsidered from the recent progress in chemistry and physics. The idea, promoting a stochastic communication hypothesis, reflects Kant’s famed insight that ‘space and time are the two essential forms of human sensibility’, translated to modern practices of quantum science. The formulation is commensurate with pioneering quantum mechanics, yet extended to take account of dissipative dynamics of open systems incorporating some fundamental features of special and general relativity. In particular we apply the idea to the class of Correlated Dissipative Structures, CDS, in biology construed to sanction fundamental processes in biological systems at finite temperatures, ordering precise spatio-temporal scales of free energy configurations subject to the Correlated Dissipative Ensemble, CDE. The modern scientific approach is appraised and extended incorporating both the material- as well as the immaterial parts of the Universe with significant inferences regarding processes governed by an evolved program. The latter suggests a new understanding of the controversy of molecular- versus evolutionary biology. It is demonstrated by numerous examples that such an all-inclusive description of Nature, including the law of self-reference, widens the notion of evolution from the micro- to the cosmic rank of our Universe.   

  • 127.
    Brändas, Erkki
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Chemistry, Department of Physical and Analytical Chemistry, Quantum Chemistry. Kvantkemi.
    A Tribute to Ilya Prigogine: (1917-2003)2004In: International Journal of Quantum Chemistry, ISSN 0020-7608, Vol. 98, p. 59-Article in journal (Other scientific)
  • 128.
    Brändas, Erkki
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Chapter 1: The Relativistic Kepler Problem and Gödel’s Paradox2012In: Progress in Theoretical Chemistry and Physics 26. Progress in Methods and Applications: Quantum Systems in Chemistry and / [ed] K. Nishikawa et al., Heidelberg: Springer, 2012, p. 3-22Chapter in book (Refereed)
    Abstract [en]

    Employing a characteristic functional model that conscripts arrays ofoperators in terms of energy and momentum adjoined with their conjugate operatorsof time and position, we have recently derived an extended superposition principlecompatible both with quantum mechanics and Einstein’s laws of relativity.We havelikewise derived a global, universal superposition principle with the autonomouschoice to implement, when required, classical or quantum representations. Thepresent viewpoint amalgamates the microscopic and the macroscopic domainsvia abstract complex symmetric forms through suitable operator classificationsincluding appropriate boundary conditions. An important case in point comes fromthe theory of general relativity, i.e. the demand for the proper limiting order at theSchwarzschild radius. In this example, one obtains a surprising relation betweenG¨odel’s incompleteness theorem and the proper limiting behaviour of the presenttheory at the Schwarzschild singularity. In the present study, we will apply ourtheoretical formulation to the relativistic Kepler problem, recovering the celebratedresult from the theory of general relativity in the calculation of the perihelionmovement of Mercury.

  • 129.
    Brändas, Erkki
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Per-Olov Löwdin - father of quantum chemistry2017In: Molecular Physics, ISSN 0026-8976, E-ISSN 1362-3028, Vol. 115, no 17-18, p. 1995-2024Article in journal (Other academic)
    Abstract [en]

    During 2016, we celebrate the 100th anniversary of the birth of Per-Olov Lowdin. He was appointed to the first Lehrstuhl in quantum chemistry at Uppsala University in 1960. Lowdin introduced quantum chemistry as a field in its own right by formulating its goals, establishing fundamental concepts, like the correlation energy, the method of configuration interaction, reduced density matrices, natural spin orbitals, charge and bond order matrices, symmetric orthogonalisation, and generalised self-consistent fields. His exposition of partitioning technique and perturbation theory, wave and reaction operators and associated non-linear summation techniques, introduced mathematical rigour and deductive order in the interpretative organisation of the new field. He brought the first computer to Uppsala University and pioneered the initiation of electronic brains' and anticipated their significance for quantum chemistry. Perhaps his single most influential contribution to the field was his education of two generations of future faculty in quantum chemistry through Summer Schools in the Scandinavian Mountains, Winter Institutes at Sanibel Island in the Gulf of Mexico. Per-Olov Lowdin founded the book series Advances in Quantum Chemistry and the International Journal of Quantum Chemistry. The evolution of quantum chemistry is appraised, starting from a collection of cross-disciplinary applications of quantum mechanics to the technologically advanced and predominant field of today, virtually used in all branches of chemistry. The scientific work of Per-Olov Lowdin has been crucial for the development of this new important province of science. [GRAPHICS] .

  • 130.
    Brändas, Erkki
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics.
    Prolate Spheroidal wavefunctions for signal processing2002In: Third International Workshop on the Dv-Xa Method, held at RIKEN, Wako, Japan, 2002Conference paper (Refereed)
  • 131.
    Brändas, Erkki
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Hoffmann, Mark
    Preface2018In: International Journal of Quantum Chemistry, ISSN 0020-7608, E-ISSN 1097-461X, Vol. 118, no 1, p. 1-2, article id e25517Article in journal (Refereed)
    Abstract [en]

    This volume collects 11 selected papers from the scientific contributions presented at the Ninth Congress of the International Society for Theoretical Chemical Physics (ISTCP-IX), organized by the team led by Professor Mark Hoffmann at the University of North Dakota, Grand Forks, North Dakota, U.S.A., from July 17 to 22, 2016. The ISTCP-IX Congress in Grand Forks followed the format established at the eight previous meetings:

     

    ISTCP-I:               Professor Ramon Carbo-Dorca, Girona (Spain), June 28 - July 3, 1993

    ISTCP-II:             Professor Sean P. McGlynn, New Orleans (LA, USA), April 9 - 13, 1996

    ISTCP-III:            Professor Miguel Castro, Mexico City (DF, Mexico), November 8 - 13, 1999

    ISTCP-IV:            Professor Jean Maruani, Marly-le-Roi (Paris, France), July 9 - 16, 2002

    ISTCP-V:             Professor Peter Politzer, New Orleans (LA, USA), July 20 - 26, 2005

    ISTCP-VI :           Professor Yan Alexander Wang, Vancouver (BC, Canada), July 19 - 24, 2008

    ISTCP-VI I:          Professor Hiromi Nakai, Waseda (Tokyo, Japan), September 2 - 8, 2011

    ISTCP-VIII:         Professor Péter Surján, Eötvös (Budapest, Hungary), August 25 – 31, 2013.

     

     

    The 2016 venue offered the possibility for the approximately 300 participants from 26 countries to join the Congress. Speakers from each of the countries were joined by students from 9 countries.  Despite being nearly 2000 km from any sea coast (1200 km, if one counts the Arctic Ocean outlet Hudson Bay),  this Congress continued to reflect the strong international characteristics of ISTCP. Countries sending 4 or more delegates include China, Denmark, France, Germany, Hungary, Israel, Japan, Mexico, Netherlands, Norway, Switzerland, and the United Kingdom, besides the U.S.A.

     

    The International Society for Theoretical Chemical Physics, ISTCP, was founded in 1990 by Professor János Ladik at the University of Erlangen, Germany. ISTCP has the objectives to promote theoretical developments at the frontier between physics and chemistry. Additionally the goal is to allow younger researchers to interact with leading contributors of the field at regularly organized International Congresses. The Society involves an Honorary Board, a Board of Directors gathering together about 60 scientists (including 5 Nobel Laureates and 2 Wolf Prize laureates) in the fields of Theoretical Chemistry and Physics, and a Board of National Representatives covering about 35 countries/regions. The current President, since July 2000, is Professor Erkki J. Brändas, from Uppsala University, Sweden.

     

    ISTCP Congress Proceedings have been published regularly in the special issues of the International Journal of Quantum Chemistry (IJQC) and partly (2002, 2008) co-published in special volumes of Progress in Theoretical Chemistry and Physics (PTCP). Following this tradition, a small and highly targeted set of articles were solicited from researchers in several forefront fields represented at ISTCP IX.  These 11 articles are divided into 4 reviews, 3 tutorial reviews, 2 perspectives and 2 papers.

     

    ISTCP-IX was organized into 9 thematic Symposia, plus a special symposium honouring Per-Olov Löwdin.  The co-organizers of each of the symposia had significant latitude in inviting leading scientists in their areas, with attention paid to overall geographical, career stage and gender diversity.  Moreover, in an effort to stimulate conversation and cross-disciplinary inquiries, each speaker was limited to only 1 talk, and there were never more than 3 parallel sessions.  It is the careful thought and hard work of the Symposium Organizers that contributed to the success of the Congress.  The Symposia and their Organizers are:

     

     1. Accurate Thermochemistry (Angela Wilson, Branko Ruscic)

     2. Chemical Insights (Paul Ayers, Pedro Salvador)

     3. Complex Systems (Jiali Gao, Nandini Ananth)

     4. Dynamics (George Schatz, Keli Han)

     5. Electronic Structure (Piotr Piecuch, Jiri Pittner)

     6. Subsystems in Density Functional Theory (Tomasz Wesolowski, Christoph Jacob)

     7. Emerging Methods for Quantum N-body Problem (Seiichiro Ten-no, Edward Valeev)

      8. Molecular Properties (Trygve Helgaker)

      9. Per-Olov Löwdin Symposium (Erkki Brändas)

    10. Relativistic Methods (Wenjian Liu, Jochen Autschbach)

     

    In addition to symposia, there were 9 plenary talks for which all participants were gathered.  The early and enthusiastic support of the plenary speakers were critical to providing high visibility for the conference, and we are grateful to them.

    1. Kim Baldridge, Structure-Property Relationships of Curved Aromatic Materials from First Principles

    2. Ria Broer, Theoretical and Computational Studies for the Design of Organic Photovoltaic Materials

    3. Benedetta Mennucci, Ab Initio Simulation of the Optical Spectroscopy of Multichromophoric Systems

    4. William Miller, Symmetrical Quasi-Classical Model for Classical Molecular Dynamics Simulations of Electronically Non-adiabatic Processes

    5. Debashis Mukherjee, A Survey of the Unitary Group Adapted MRCC and MRPT Theories: SU vs SS Approaches

    6. Martin Quack, The Quantum Dynamics of Chiral and Achiral Molecules including Electroweak Parity Violation: Theory and Experiment

    7. Andreas Savin, Multireference Density Functional Theory

    8. Henry F. Schaefer III

    9. Tamar Seideman, Coherent Alignment in Complex Systems

     

    This Preface does not allow a comprehensive account of all the excellent contributions to the conference or to the articles submitted to these proceedings. The 4 Reviews consider relativistic treatment of molecular properties, charge transfer in molecular crystals and in organic polymeric materials, and advances in subsystem embedding.  These are complemented by Tutorial Reviews on molecular motors, the inverse approach to exchange-correlation potentials, and the random phase approach in the context of reduced density matrices.  One full paper considers the chemistry of new super heavy elements and the other on data considerations in petascale computations of chemical and biological systems.  There are Perspectives on non-collinear electronic structure calculations and calculations of atoms and molecules in strong magnetic fields.  The articles in the proceedings can be grouped roughly into extension of theory and calculations into much larger systems than could be considered just a few years ago and extension of precision in theory and calculations.

     

    We are grateful to all organizers for their exceptional work. In particular we want to thank Professor Janos Ladik, Founder of the Society and Honorary Chair. We were sorry to learn that he could not participate in person but his kind interest and strong support in the various matters of the venue were indeed a positive factor. We are indebted to our excellent organizing committee that guided us in producing a well-balanced, global perspective on cutting-edge chemical physics: Gustavo Aucar, T. Daniel Crawford, Peter Gill, Anna Krylov, Hiromi Nakai, Katarzyna Pernal, Péter Surján and Ágnes Szabados. We are also grateful to all session chairs, speakers, poster presenters, as well as all student volunteers, contributing significantly to the great success of the meeting. For more details regarding the Congress we refer to our web site http://istcp-2016.org/.

     

    The ISTCP-IX Congress took place at the Alerus Center, near the University of North Dakota campus. The assistance of the staff at the Alerus Center and at the Greater Grand Forks Convention and Visitors Bureau were critical in facilitating an event of this complexity in this city of only 60,000 people.  But, most of all, it was the unwavering support of former UND President Robert Kelley, Vice President of Academic Affairs and Provost Tom DiLorenzo, Vice President for Research and Economic Development Grant McGimpsey, and Division of Research Staff Cathy Lerud and Carla Kellner that made this happen.

     

    We are pleased to express our sincere thanks to our sponsors.  In addition to generous support from the University of North Dakota and the Greater Grand Forks Convention and Visitors Bureau, which allowed low-cost registration and accommodations for students, we are pleased to be able to acknowledge additional support from Physical Chemistry Chemical Physics and Department of Energy. These contributions from our sponsors have enabled us to maintain the high-quality standard of the Congress.

     

    The guest editors of this Special Issue, finally, want to thank the authors, who accepted our invitation to contribute to these proceedings, and in so doing provide a perspective of some cutting edge areas of inquiry in chemical physics.  The IXth Congress of ISTCP included both these areas and many more. We hope that all researchers with a great interest in theory and methods related to fundamental scientific problems and future progress of our field will appreciate this volume.

     

    Mark Hoffmann

    Erkki Brändas

     

     

  • 132.
    Brändas, Erkki J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    A Zero Energy Universe Scenario: From Unstable Chemical States to Biological Evolution and Cosmological Order2015In: Frontiers In Quantum Methods And Applications In Chemistry And Physics / [ed] Nascimento, MAC; Maruani, J; Brandas, EJ; DelgadoBarrio, G, Heidelberg: Springer, 2015, Vol. A29, p. 247-284Conference paper (Refereed)
    Abstract [en]

     A Zero-Energy Universe Scenario (ZEUS) is portrayed and its implications are examined and clarified. The formulation is based on the algebra of observables, e.g. the momentum-energy and their canonical conjugate partner space-time. Operators represent them in quantum theory and classical canonical variables in nonquantum applications. Conjugate operator/variable arrays impart a united edifice for a zero-energy universe scenario, which corresponds to using a non-positive definite metric for the manifestation of unstable states as recently employed in the field of chemical physics. Analogous formulations within a general complex symmetric setting provide a compelling analogy between Einstein s theory of general gravity and Gödel s first incompleteness theorem. This scenario brings together up-to-date theories in chemical physics with modern research in biology, physics, and astronomy. This unification establishes an edifice for the various arrows of time as well as authenticates Darwin s Paradigm of Evolution from the microscopic realm to the cosmological domain.

  • 133.
    Brändas, Erkki J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Arrows of Time and Fundamental Symmetries in Chemical Physics2013In: International Journal of Quantum Chemistry, ISSN 0020-7608, E-ISSN 1097-461X, Vol. 113, no 3, p. 173-184Article in journal (Refereed)
    Abstract [en]

    The field of chemical and physical processes, using principal microscopic techniques, should today allegedly be identified as a fundamental branch of physics. The discipline, by tradition known as chemical physics, is undergoing rapid progress. This assessment, illustrated by the advances presented at this Congress, is characterized by modern developments and novel trends with a concrete bearing on original theoretical understanding, with the possibility to go beyond traditional interpretations and explanations. In this vein, we do not only consider nonrelativistic treatments of various types of molecules including interactions between these and polymers, theoretical examinations of chemical reactions, surface states and interface states, disordered phenomena etc., but also recent progress together with non-Hermitian extensions to quantum mechanics and statistical mechanics. The latter leads to a united edifice of theoretical constructions including the law of self-reference, which emerges in analogy with the illustrious Gödel theorem(s) of mathematical logic, that is, the assertion of the inherent limitations of all nontrivial axiomatic systems. The current development begets the foundation of temporal processes and associated invariance principles including the valuation of the various arrows of time. The present conjugate operator array formulation supports the possible gravitational origin of molecular chirality and other principal symmetry violations.

  • 134.
    Brändas, Erkki J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry, Quantum Chemistry.
    Complex Symmetric Forms and the Emergence of Jordan Blocks in Analytically Extended Quantum Theory2009In: International Journal of Computer Mathematics, ISSN 0020-7160, E-ISSN 1029-0265, Vol. 86, no 2, p. 315-319Article in journal (Refereed)
    Abstract [en]

    The justification and rationale for analytically continuing quantum mechanics into the complex plane are recognized and briefly discussed. This extension is described by a complex symmetric representation, which is derived and demonstrated to include general Jordan block forms of Segre characteristics larger than one. Various applications in physics and chemistry, in which this extension appears necessary, are pointed out.

  • 135.
    Brändas, Erkki J
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry, Quantum Chemistry.
    Complex Symmetry, Jordan Blocks and Microscopic Selforganization: An Examination of the Limits of Quantum Theory. Based on Nonself-adjoint Extensions with Illustrations from Chemistry and Physics2009In: Self-Organization of Molecular Systems: From Molecules and Clusters to nanotubes and Proteins / [ed] N. Russo, V. Ya. Antonchenko, E. Kryachko, Springer , 2009, p. 49-87Chapter in book (Refereed)
    Abstract [en]

    The basis and motivation for extending quantum mechanics beyond its traditional domain are recognized and examined. The mathematical details are briefly discussed and a convenient compact complex symmetric representation derived. An original formula is proved and demonstrated to incorporate general Jordan block configurations characterized by Segrè characteristics larger than one. It is verified that these triangular forms can portray realistic evolutions via maps established both within fundamental quantum mechanics as well as within a generalized thermodynamic formulation displaying features that are reminiscent of self-organization on a microscopic level. Various applications of these so-called coherent dissipative structures in physics and chemistry are pointed out, and discussed with possible inferences also made to the biological domain.

  • 136.
    Brändas, Erkki J.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics.
    Dissipative Systems and Microscopic Selforganization2002In: Advances in Quantum Chemistry, ISSN 0-12-034841-1, Vol. 41, p. 121-Article in journal (Refereed)
  • 137.
    Brändas, Erkki J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Frontiers in Quantum Methods and Applications in Chemistry and Physics: Selected Proceedings of QSCP-XVIII (Paraty, Brazil, December, 2013)2015 (ed. A29)Book (Refereed)
    Abstract [en]

    This volume collects 15 selected papers from the scientific contributions presented at the Eighteenth International Workshop on Quantum Systems in Chemistry, Physics, and Biology (QSCP-XVIII), which was organized by Prof. M.A.C. Nascimento at the Casa da Cultura in Paraty (Rio de Janeiro), Brazil, from December 1 to 7, 2013. Over 100 scientists from 25 countries attended this meeting. Participants of the QSCP-XVIII workshop discussed the state of the art, new trends, and future evolution of methods in molecular quantum mechanics, and their applications to a wide variety of problems in chemistry, physics, and biology. The high-level attendance attained in this conference was particularly gratifying. It is the renowned interdisciplinary nature and friendly feeling of QSCP meetings that make them such successful discussion forums. Paraty is located in the south coast of Brazil, 250 km from Rio de Janeiro, the state capital. This historical town, nestled on the Costa Verde, is a living memory of the Gold Cycle: gold extracted from the mines of the state of Minas Gerais was transported by mule along the Estrada Real down to Paraty and from there shipped to Rio de Janeiro. The area of Paraty is probably the only place on the planet that brings together a native forest about 80 % preserved, a bay protected from the open sea by over a hundred islands, and a seventeenth-century town which is regarded by UNESCO as the most harmonious baroque location in the world. From this past originate the relics and traditions that so enchant the visitors: a wonderful wealth of cultural and ecological attractions, as well as a tourist infrastructure consisting of cosy inns and picturesque restaurants. Details of the Paraty meeting, including the scientific program, can be found on the web site: http://www.qscp2013.iq.ufrj.br. Altogether, there were 18 morning and afternoon sessions, where 55 plenary talks were given, and two evening poster sessions, with 18 fl ash presentations for a total of 38 displayed posters. We are grateful to all participants for making the QSCP-XVIII workshop a stimulating experience and a great success. QSCP-XVIII followed the traditions established at previous workshops:

     QSCP-I, organized by Roy McWeeny in 1996 at San Miniato (Pisa, Italy);

    QSCP-II, by Stephen Wilson in 1997 at Oxford (England);

    QSCP-III, by Alfonso Hernandez-Laguna in 1998 at Granada (Spain);

    QSCP-IV, by Jean Maruani in 1999 at Marly-le-Roi (Paris, France);

    QSCP-V, by Erkki Brä ndas in 2000 at Uppsala (Sweden);

    QSCP-VI, by Alia Tadjer in 2001 at Sofi a (Bulgaria);

    QSCP-VII, by Ivan Hubac in 2002 near Bratislava (Slovakia);

    QSCP-VIII, by Aristides Mavridis in 2003 at Spetses (Athens, Greece);

    QSCP-IX, by Jean-Pierre Julien in 2004 at Les Houches (Grenoble, France);

    QSCP-X, by Souad Lahmar in 2005 at Carthage (Tunisia);

    QSCP-XI, by Oleg Vasyutinskii in 2006 at Pushkin (St Petersburg, Russia);

    QSCP-XII, by Stephen Wilson in 2007 near Windsor (London, England);

    QSCP-XIII, by Piotr Piecuch in 2008 at East Lansing (Michigan, USA);

    QSCP-XIV, by Gerardo Delgado-Barrio in 2009 at El Escorial (Madrid, Spain);

    QSCP-XV, by Philip Hoggan in 2010 at Cambridge (England);

    QSCP-XVI, by Kiyoshi Nishikawa in 2011 at Kanazawa (Japan);

    QSCP-XVII, by Matti Hotokka in 2012 at Turku (Finland).

    The lectures presented at QSCP-XVIII were grouped into nine areas in the field of Quantum Systems in Chemistry, Physics, and Biology , ranging from Concepts and Methods in Quantum Chemistry and Physics through Molecular Structure and Dynamics, Reactive Collisions and Chemical Reactions, to Computational Chemistry, Physics, and Biology. The width and depth of the topics discussed at QSCP-XVIII are refl ected in the contents of this volume of proceedings in the book series Progress in Theoretical Chemistry and Physics, which includes four sections:

    I. Quantum Methodology (3 papers);

    II. Structure and Properties (4 papers);

    III. Molecular Dynamics (4 papers);

    IV. Fundamental Theory (3 papers).

    In addition to the scientifi c program, the workshop had its usual share of cultural events. There was a boat cruise in the Paraty bay and a show by the internationally known group Contador de Estórias . The award ceremony of the CMOA Prize and Medal took place during the congress banquet in the most traditional restaurant of Paraty, Margarida Café. The CMOA Prize was shared between two selected nominees: Jer-Lai Kuo and Yuan-Chung Cheng, both from Taiwan. Two other nominees, Jhih-Wei Chu (from Taiwan) and Andriy Loboda (from Ukraine) received a certifi cate of nomination and a gift. The prestigious CMOA Medal for senior scientists was awarded to Prof. Lorentz Cederbaum (University of Heidelberg, Germany). According to a custom of QSCP meetings, the venue of the next yearly workshop was announced to be in Odessa, Ukraine, in 2015, followed by one in Taipei, Taiwan, in 2016. However, due to the political events, the dates of the two meetings were later reversed. We are pleased to acknowledge the generous support given to the QSCP-XVIII conference by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), the City of Paraty Convention Bureau and Casa da Cultura  of Paraty. We are most grateful to all members of the Local Organizing Committee for their work and dedication, which made the stay and work of participants both pleasant and fruitful. We also thank the members of the International Scientifi c Committee and the Honorary Committee for their invaluable expertise and advice. We hope the readers will fi nd as much interest in consulting these proceedings as the participants in attending the meeting.

    M.A.C. Nascimento

    Jean Maruani

    Erkki J. Brändas

    Gerardo Delgado-Barrio

  • 138.
    Brändas, Erkki J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Quantum Chemistry.
    Microscopic self-organization and self-referential systems: a progress report.2009In: International Journal of Quantum Chemistry, ISSN 0020-7608, E-ISSN 1097-461X, Vol. 109, no 14, p. 3500-3504Article in journal (Refereed)
    Abstract [en]

    It is contended that (the classical canonical form of) Jordan blocks, play a role analogous to those of paradoxes and self-referential contradictions in philosophy and mathematical logic. As examples we will briefly discuss the occurrence of such triangular units in appropriately generalized quantum theory of microscopic as well as open dissipative systems with structures appearing on both the fundamental as well as in higher order levels of organization. The mathematical structure centers on specific transformations within coherent-dissipative ensembles that exhibit certain factorization properties allowing prime number algorithms, cf. the Godel encoding system used to derive the celebrated incompleteness theorem. This prompts the suggestion that an additional meta-code, cf. the genetic code, might be a-scripted for the mapping between the genotype and phenotype spaces.

  • 139.
    Brändas, Erkki J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Molecular theory of the genetic code2018In: Molecular Physics, ISSN 0026-8976, E-ISSN 1362-3028, Vol. 116, no 19-20, p. 2622-2632Article in journal (Refereed)
    Abstract [en]

    This article honours Michael Baer on the occasion of his 80th birthday and celebrates his scientific contributions to non-adiabatic chemical physics. This undertaking prompts the presentation of a first principles molecular theory of the genetic code. Jacques Monod's classic essay, 'Chance and Necessity', is exercised as a platform for this discussion. In particular the controversial concept of teleonomy is considered and evaluated in relation to modern developments in chemical physics.

  • 140.
    Brändas, Erkki J.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Quantum Chemistry. ADVANCED INSTRUMENTATION AND MEASUREMENTS.
    New Perspectives in Theoretical Chemical Physics2003In: Advances in Quantum Chemistry, ISSN ISBN: 0-12-034843-8, Vol. 42, p. 383-398Article in journal (Refereed)
  • 141.
    Brändas, Erkki J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Preface2015In: Advances in Quantum Chemistry, Amsterdam: Academic Press, 2015, , p. 425Chapter in book (Other academic)
    Abstract [en]

    PREFACE

     

    Advances in Quantum Chemistry provides researchers in quantum chemistry, physical chemistry and chemical physics with up-to-date surveys, invited reviews and highlights of recent achievements. Although the field of quantum chemistry has emerged as a subject of its own it overlaps fundamentally with other fields like applied mathematics, theoretical biology, signal processing including applications in medicine.

    In the present volume, the readers are presented with an exciting combination of themes, i.e. a description of anti-ferromagnetism in copper oxide, proton-conducting mechanism in solid oxide fuel cells, time-dependent processes in molecular processes, the essence of chemical bonding, biological models for repair of cellular radiation damage, momentum space methods for accurate molecular electronic structure calculations and functional theoretic models for hydrogen bonding networks and proton wires in water oxidation reactions.

     

    The first chapter in this volume Chapter, by Kimichika Fukushima, deals with the description of antiferromagaetism in copper oxides using density functional theory.  This is a longstanding problem, and the solution is discussed in terms of the variational method based SIWB (surrounding or solid Coulomb-potential-induced well for basis set) scheme.  The characteristics of the well stabilizing the O2- ion and making antiferromagaetism possible are discussed.

     

    In the second chapter Taku Onishi investigates proton-conducting mechanisms in solid electrolyte oxide fuel cells. Specifically LaAlO3 perovskite is allegedly proposed and compared with conventional perovskite-type conductors. The analysis, based on hybrid Kohn-Sham density functional theory, characterizing the proton conducting pathways, confronts mechanism elucidation and material design, including safety aspects regarding the conflicts with oxide ion conduction. In particular as the oxygen vacancy, doped to incorporate the proton, may conflict with oxide ion conduction, it was concluded, when utilizing LaAlO3 that the temperature strictly regulates the prevention of coincident oxide ion conduction.

     

    In Chapter 3, Yngve Öhrn presents and discusses a time dependent treatment of molecular processes.  The scheme, known as electron nuclear dynamics (END), is described in formal detail wich includes the choice of coordinate system and its effect on the molecular Hamiltonian, the choice of molecular wave function and the particular role of the time-dependent parameters that originates in a coherent state representation is discussed.  References are given to some of the work done with ENDYNE.

     

    Chapter 4 concerns chemical bonding. In the present contribution, Elena Sheka describes her experiences of chemical bonds in various investigations of structural chemistry. The investigations comprise a rich selection of chemical compounds from single, double and triple bonds, involving carbon, to provoking the main issues of modern chemistry devoted to fullerenes and recently graphene, the famous nobeliated 2D solid. The structures investigated permit a rather simple methodology based on the odd electron strategy, predominantly advocated by the author.

     

    In chapter 5, Dževad and Karen Belkić, advance their notable input to a far-reaching and across-the-board biophysical and chemical analysis of surviving fractions of irradiate cells and their new mechanistic repair-based Padé linear-quadratic model, PLQ. As current dose planning systems in radiotherapy, based on linear-quadratic models (LQ), is satisfactory only at low doses and inadequate for treatment modalities, or hyperfractionation, it is demonstrated that PLQ significantly outperforms LQ models regarding cell survival fractions including saturation effects.

     

    Although Gaussian technology has greatly simplified mainstream quantum chemistry, it is a cognizant fact that exponential-type orbitals, ETO’s, are better suited for molecular electronic structure calculations. In chapter 6, James and John Avery contribute to new progress in quantum chemistry by using Fock’s projection of 3D momentum space to 4D hyperspherical harmonics. The authors exploit their extraordinary competence in treating so-called Coulomb Sturmians to derive a general mathematical theorem including elegant, rapid and accurate evaluations of appropriate quantum mechanical molecular integrals. The ensuing closed form expression is illustrated by adequate examples.

     

    The final contribution to this volume, Chapter 7 by Yamaguchi et al., uses a QM/MM method to calculate complicated properties of water oxidation in the biosystem known as photosystem II (PSII).  Water oxidation in the oxygen evolving complex of PSII is dependent on the hydrogen-bonding networks.  The QM/MM computations elucidate the network structures: hydrogen–bonding O…. O(N) and O…H distances and O(N)-H…O angles in PRP, together with the Cl-O(N) and Cl…H distances and O(N)-H…Cl angles for chloride anions.  The results are compared with experiment.

     

    As advertised, the contents of this volume are multifarious as regards both fundamental theory and innovative applications. The contributing authors have made great strides to share their insights with the reader of the Advances. As series editors, we hope that the present volume will impart the same pleasure and enjoyment as we faced during the preparation of this volume.

     John R. Sabin and Erkki J. Brändas

  • 142.
    Brändas, Erkki J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry, Quantum Chemistry.
    The equivalence principle from a quantum mechanical perspective2009In: Advances in the theory of atomic and molecular systems / [ed] P. Piecuch, J. Maruani, G. Delgado-Barrio, S. Wilson, Springer Netherlands, 2009, p. 73-92Chapter in book (Other academic)
  • 143.
    Brändas, Erkki J
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. ADVANCED INSTRUMENTATION AND MEASUREMENTS.
    Kryachko, Eugene S.
    Fundamental World of Quantum Chemistry: A Tribute to the Memory of Per-Olov Löwdin: Foreword to Volume I2003In: Fundamental World of Quantum Chemistry, Vol. I, p. vii-viiiOther (Other scientific)
  • 144.
    Brändas, Erkki J
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Quantum Chemistry. ADVANCED INSTRUMENTATION AND MEASUREMENTS.
    Kryachko, Eugene S.
    Fundamental World of Quantum Chemistry: A Tribute to the Memory of Per-Olov Löwdin: Foreword to Volume II2003In: Fundamental World of Quantum Chemistry, Vol. II, p. vii-viiiOther (Other scientific)
  • 145.
    Brändas, Erkki J
    et al.
    Uppsala University.
    Kryachko, Eugene S.
    Uppsala University.
    Fundamental World of Quantum Chemistry: A Tribute to the Memory of Per-Olov Löwdin: Volume I2003In: Fundamental World of Quantum Chemistry, Vol. I, p. 1-677Book (Refereed)
  • 146.
    Brändas, Erkki J
    et al.
    Uppsala University.
    Kryachko, Eugene S.
    Uppsala University.
    Fundamental World of Quantum Chemistry: A Tribute to the Memory of Per-Olov Löwdin: Volume II2003In: Fundamental World of Quantum Chemistry, Vol. II, p. 1-696Book (Refereed)
  • 147.
    Brändas, Erkki J.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Materials Science. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry.
    Levitina, Tatiana
    Filter Diagonalization: filtering and postprocessing with prolates.2009In: Computer Physics Communications, ISSN 0010-4655, E-ISSN 1879-2944, Vol. 180, no 9, p. 1448-1457Article in journal (Refereed)
    Abstract [en]

    A detailed account is given of a recent modification of the Filter Diagonalization technique that serves to analyze a signal spectrum within a selected energy range. Our approach employs for filtering the eigenfunctions of the Finite Fourier Transform, or prolates, which are superior to other filters due to their special properties. In particular, prolates are simultaneously band-limited and highly concentrated at a finite time-interval, producing filters with optimal accuracy. In addition both features are acquired by the convolution of a band-limited function with a prolate, that permits the latter to be interpolated via the Walter and Shen sampling formula, which essentially simplifies the supplementary computations. Rigorous filtering error estimates are obtained. Test calculations illustrate the facilities of the presented modification.

  • 148.
    Brändas, Erkki J.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Lunell, Sten
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Theoretical Chemistry.
    Obituary: Osvaldo Goscinski (1938–2013)2015Other (Other academic)
  • 149.
    Brändas, Erkki J
    et al.
    Uppsala University.
    Öhrn, Yngve
    Uppsala University.
    International Journal of Quantum Chemistry2003In: International Journal of Quantum Chemistry, Vol. 91-95, no 1-6, p. 1-4000Other (Other scientific)
  • 150.
    Brändas, Erkki
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Chemistry, Department of Physical and Analytical Chemistry, Quantum Chemistry. Kvantkemi.
    Kryachko, Eugene
    Preface: A Tribute Volume in Honour of Professor Osvaldo Goscinski2004In: Advances in Quantum Chemistry, ISSN 0065-3276, Vol. 47, p. xvii-xviiiArticle in journal (Other scientific)
1234567 101 - 150 of 1248
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