Investigation of crown ether cation systems using electrophoretic NMR
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
The purpose of this thesis was to investigate how crown ethers behave and interact with different cations and to optimise the setup of the electrophoretic NMR. To get a good electrophoretic NMR measurement the electrophoretic phase shift needs to be big. To increase the phase shift some parameters needed to be adjusted, parameters such as the concentration of crown ether and cation, the duration of magnetic field gradient pulse δ, the magnetic field gradient strength g, the diffusion time Δ and the applied voltage V.
The main focus then put on crown ethers 15-crown-5 and 18-crown-6. The cations used were lithium (Li), sodium (Na), potassium (K), caesium (Cs), calcium (Ca) and barium (Ba).
The effective charge was obtained by using pulsed gradient NMR to derive the diffusion coefficient and electrophoretic NMR to get the electrophoretic mobility. These data were used to calculate the equilibrium constant of the formed complex.
The outcome of the investigation: the affinity for 18-crown-6 was in the following order
barium > potassium > caesium > sodium > calcium > lithium
and for 15-crown-5
barium > sodium > calcium > caesium > potassium > lithium.
Place, publisher, year, edition, pages
2012. , 48 p.
electrophoretic NMR, diffusion NMR, crown ether, electrophoretic mobility and equilibrium constant
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-156315OAI: oai:DiVA.org:kth-156315DiVA: diva2:766170