How π back-donation quantitatively controls the CO stretching response in classical and non-classical metal carbonyl complexes† †Electronic supplementary information (ESI) available: Additional figures and DFT-optimized XYZ geometries for all the co

How π back-donation quantitatively controls the CO stretching response in classical and non-classical metal carbonyl complexes† †Electronic supplementary information (ESI) available: Additional figures and DFT-optimized XYZ geometries for all the co