Vibrational spectra and force constants of the hexacarbonyls of chromium, molybdenum and tungsten

摘要: Abstract The infrared absorption spectra of the hexacarbonyls Cr, Mo, and W have been observed in gaseous solid states. Eleven thirteen fundamental frequencies each assigned. Force constants were calculated using a resonance interaction potential function. order metal carbon force is F WC > CrC MoC . For these three it found that higher metal-carbon constant accompanied by lower CO constant, indicating decrease metal—ligand π bonding same as constants. various are discussed. They all reasonable values except non-coplanar MCO, MCO bending constants, which unexpectedly large. results this work support use valence field for molecules sort.