indico  First event Previous event Thesis defense Next event Last event   | view:  |  manage export to personal scheduler  | 
user login 

 

Licentiate Thesis: Zero-Field Splitting in Gd(III) complexes
  Thesis defense

Thursday 07 January 2016
from 10:00 to 12:00
at FP41
Speaker : Shehryar Khan (Stockholm University, Department of Physics)
Abstract : The prime objective of contrast agents in Magnetic Resonance Imaging(MRI) is to accelerate the relaxation rate of the solvent water protons in the surrounding tissue. Paramagnetic relaxation originates from dipole-dipole interactions between the nuclear spins and the fluctuating magnetic field induced by unpaired electrons. Currently, Gadolinium(III) chelates are the most widely used contrast agents in MRI, and therefore it is incumbent to extend the fundamental theoretical understanding of parameters that drive the relaxation mechanism in these complexes. Traditionally, the Solomon-Bloembergen-Morgan equations have been utilized to describe relaxation times in terms, primarily of the Zeeman interaction, which is the splitting of degenerate energy levels due to an applied magnetic field. However, in compounds such as Gadolinium(III) complexes with total electron spins higher than 1 (in this case S=7/2) other interactions such as the Zero-Field Splitting(ZFS) play a significant role. ZFS is the splitting of degenerate energy levels in the absence of an external magnetic field. For this purpose, the current research delves into an understanding of the relaxation process, focusing on ZFS in various complexes of interest, using quantum chemical methods as well as molecular dynamic simulations.

AlbaNova  | Last modified 17 December 2015 09:27  |  HELP