Diamagnetic behaviour of high-resolution nitrogen-14 nuclear magnetic resonance spectra for co-ordinated nitrogens in paramagnetic chromium(III) diamine complexes

Abstract

Diamagnetic behaviour in the chemical shift and linewidth of high-resolution nitrogen-14 NMR spectra for paramagnetic chromium(III) diamine complexes was investigated in comparison with that for the corresponding diamine dihydrochlorides and the diamagnetic cobalt(III) complexes. The NMR signals can be assigned to each inequivalent nitrogen ligating atom of unsymmetic diamines in the chromium(III) complexes. The ¹⁴N NMR spectra are affected by the diamine chelate ring conformations of the tris(diamine) complexes, but hardly sensitive to the ligand replacement in trans- and cis-[CrX₂(diamine)₂] type complexes.