Cobalt-59 nuclear magnetic resonance study of µ-carboxylato-di-µ-hydroxo-bis[triamminecobalt(III)] complexes

Abstract

⁵⁹ Co N.m.r. spectra of 24 µ-carboxylato-di-µ-hydroxo-bis[triamminecobalt(III)] complexes have been examined. Chemical-shift values are constant for all the complexes. However, the linewidths differ significantly. It is shown that the ⁵⁹Co relaxation is a function of the basicity of the oxygen atoms of the symmetrically bonded carboxylate bridging groups (affecting the electric-field gradient at the Co nuclei) and of the size and shape of the complexes (affecting the rotation-correlation time).