INFRARED SPECTROSCOPIC INVESTIGATION OF PYRIDINE-2-CARBOXAMIDE CHELATES OF BIVALENT METALS .I. SYNTHESES OF CHELATES AND THEIR INFRARED SPECTRA IN REGION 4000-200 CM-1

the chelates of pyridine-2-carboxamide(piaH) studied were the following two types: non-ionic [M(pia)2] and cationic [M(H2O)2(piaH)2]X2 (M = Co, Cu, Fe, Ni and Pd). Vibration assignments were made on the empirical basis, on considering the changes of frequency with central metal ions, and substitution of N and H atoms of the ligand with 15N and D respectively. The cationic chelates were found to have the N,O-co-ordination, while the non-ionic chelates The N,N-co-ordination. © 1969.