A New Method for Analyzing the Force Constants of Tricarbonyl Complexes with CS Symmetry

Metal carbonyl complexes that generally used as catalyst in early researches have attracted much attention recently due to their potential pharmaceutical applications as CMIA and CORMs. Metal carbonyls also have used also as bioprobe, protein-labelling agent thanks to unique spectroscopic feature in mid-IR. The position and the number of carbonyl IR bands have affected by chemical environment of carbonyl unit and coordinated ligands. Therefore, the force constants of metal carbonyl complexes could give meaningful qualitative and quantitative information about the electronic influences of the coordinated ligands. Additionally the force constants could be useful criteria when the carbonyl ligands have evaluated in terms of isolobal analogy. In this study, the stretching and the interaction force constants of many metal carbonyl complexes with lots of different seconder ligands have calculated with a new suggested simple method to gain insight into the σ-donor/π-acceptor properties of these coordinated ligands