Carbon‐13 spin–lattice relaxation study on molecular dynamics of some penta‐ and tricarbonylchromium complexes

Abstract

Carbon-13 spin-lattice relaxation times were measured for some penta-and tricarbonylchromium complexes of organic ligands. The chemical shift anisotropy of the carbonyl carbons was estimated to be cu. 500 ppm. The contributions of dipoledipole and chemical shift anisotropy mechanisms to the overall relaxation were evaluated and used to determine the reorientational parameters for the ligand and carbonylchromium moieties. It seems that the internal rotation rate about the ligand+hromium bond is governed mainly by intermolecular interactions.