title: Vibrational dynamics of zero-field-splitting hamiltonian in gadolinium-based MRI contrast agents from ab initio molecular dynamics.
abstract: The electronic relaxation of gadolinium complexes used as MRI contrast agents was studied theoretically by following the short time evolution of zero-field-splitting parameters. The statistical analysis of ab initio molecular dynamics trajectories provided a clear separation between static and transient contributions to the zero-field-splitting. For the latter, the correlation time was estimated at approximately 0.1 ps. The influence of the ligand was also probed by replacing one pendant arm of our reference macrocyclic complex by a bulkier phosphonate arm. In contrast to the transient contribution, the static zero-field-splitting was significantly influenced by this substitution.
authors.affiliation: DSM/IRAMIS/NIMBE (CEA-CNRS UMR3299), Commissariat à l'Énergie Atomique, 91191 Gif-sur-Yvette, France.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Lasoroski
authors.affiliation: École Normale Supérieure, Département de Chimie, ENS-CNRS-UPMC UMR8640, 75005 Paris, France.
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Vuilleumier
authors.affiliation: DSM/IRAMIS/NIMBE (CEA-CNRS UMR3299), Commissariat à l'Énergie Atomique, 91191 Gif-sur-Yvette, France.
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Pollet
mesh_terms: D003287:Contrast Media / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D005682:Gadolinium / Q000737:chemistry*; D006801:Humans; D008024:Ligands; D008279:Magnetic Resonance Imaging; D056004:Molecular Dynamics Simulation; D014732:Vibration
chemical_list: D003287:Contrast Media; D008024:Ligands; D005682:Gadolinium