THE VIBRATIONAL SPECTRA OF TRANSITION METAL MONOCARBONYLS MOLECULES

Author Institution: L.A.D.I.R./Spectrochimie Moleculaire, U.M.R. 7075, CNRS-Universite Pierre et Marie CurieThe infrared spectrum of MCO molecules (M=Co, Ni, Pd, Pt, and Cu) isolated in solid argon has been reinvestigated. Various isotopic data ($^{12}C/^{13}C, ^{16}O/^{18}O$, natural isotopes for the metal) on $v_{1}, v_{2}, v_{3}$ and number of two quantum transitions have been measured in the near- and far-infrared regions. This enables a complete harmonic force-field calculation based on calculated geometry can be estimated. Comparisons of spectroscopic parameters for the Ni-, Pd-, PtCO and Co-, Ni-, CuCO series, experimental binding energies and the latest ab initio predictions are also presented. The bond force constants can be compared and the results show that the pertubations of the CO ligand are very unreliable indicators of the evolution of the binding energies, contrary to the metal-carbon force constant