Spectroscopic and theoretical investigations of vibrational frequencies in binary unsaturated transition-metal carbonyl cations, neutrals, and anions

Vibrational frequencies in binary unsaturated transition-metal carbonyl cations, neutrals and anions were investigated spectroscopically and theoretically. Neon matrix investigations provided carbonyl cations and anions for comparison to neutrals. Density functional theory (DFT) was used to calculate different isotopic frequencies and isotopic frequency ratios were computed as a measure of normal vibrational mode in the molecule. The bonding trends for all metals showed that the C-O stretching frequencies followed the order cations>neutrals>anions.