BAND ASSIGNMENTS IN THE IR-SPECTRUM OF CIS,CIS-BIS(GLYCINATO)CIS-BIS(IMIDAZOLE)NICKEL(II) BY MULTIPLE ISOTOPIC LABELING

The i.r. spectra of cis-[Ni(gly)2(Him)2] (gly = glycinate ion, Him = imidazole) and its isotopically-labelled analogues have been determined over the range 4000-150 cm-1. 18O-, 15N-, 1-13C-, 2-13C-, and 2,2-d2-labelling of the coordinated glycinate yields assignments for the internal glycinate modes and the nickel-oxygen and nickel-nitrogen stretching and bending vibrations while deuteration of imidazole (Him-d3) provides assignments for the internal modes of the coordinated imidazole rings and for the nickel-imidazole vibrations. The results, combined with those of previous multiple isotopic labelling studies on glycinate complexes, enable some general conclusions to be reached on the i.r. spectra of these compounds. © 1979.