Vibrational scaling factors for transition metal carbonyls

• Published in: Chemical physics letters 2015-11, Vol.640 (C), p.175-179
• Main Authors: Assefa, M.K., Devera, J.L., Brathwaite, A.D., Mosley, J.D., Duncan, M.A.
• Format: Article
• Language: English
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2015.10.031

•20 metal carbonyl complexes are investigated with density functional theory.•Four functionals (B3LYP, BP86, M06, and M06-L) and three basis sets are employed.•Compared theoretical vs experimental frequencies yield vibrational scaling factors.•Scaled computed vibrations are compared to multiplet patterns in carbonyl spectra.•No functional has a clear advantage over others with respect to vibrational patterns. Vibrational frequencies for a selected set of transition metal carbonyl complexes are computed with various forms of density functional theory (B3LYP, BP86, M06, and M06-L), employing several different basis sets. The computed frequencies for the carbonyl stretches are compared to the experimental values obtained from gas phase infrared spectra of isolated neutrals and ions. Recommended carbonyl-stretch scaling factors which are developed vary significantly for different functionals, but there is little variation with basis set. Scaled frequencies compared to experimental spectra for cobalt and tantalum carbonyl cations reveal additional variations in multiplet patterns and relative band intensities for different functionals.