Spectroscopic and theoretical study of [PdCl3(C2H4)](-) and [PdCl3(C2D4)](-) complexes

FTIR and FT-Raman spectra of [PdCl3(C2H4)](-) and [PdCl3(C2D4)](-) anions h ave been recorded at greater sensitivity than hitherto and assigned on the basis of the well-studied Zeise's salt. Density functional theory (DFT) cal culations were performed in order to obtain the optimised geometry, the vib rational frequencies and IR intensities of the Pd-complex. The comparison o f the theoretical infrared spectra, the H/D isotopic shifts and the shifts in the CC stretching and CH scissoring frequencies upon coordination with t hose from experimental study show a remarkable agreement for the [PdCl3(C2H 4)](-) and [PdCl3(C2D4)](-) species. The optimised PdC bond distance is 2.1 97 Angstrom, indicating that the metal ligand bond is weaker in [PdCl3(C2H4 )](-) than in Zeise's salt but C2H4 seems to be more distorted in the Pd-an alogue. The calculated force constants also confirm the lower stability of the Pd-complex. (C) 1999 Published by Elsevier Science S.A. All rights rese rved.