Proton-deuterium isotope shifts in ⁵⁹Co N.M.R.

Abstract

An isotope shift of 5 ppm per deuterium atom has been observed for the ⁵⁹Co resonance of tris(ethylenediamine)cobalt(III) chloride ([Co(en)₃]Cl₃) and hexaamminecobalt(III) chloride([Co(NH₃)₆]Cl₃) after exchange of hydrogen for deuterium. The upfield direction of the shift can be readily understood as changes in the ligand-field strength causing changes in the nuclear paramagnetic screening.