Theoretical investigations of the structure and bonding of several transition metal complexes to probe their carbon monoxide releasing properties.

The structural and bonding characteristics of several CO-releasing molecules have been investigated using density functional theories. Based on the nature of the physiological buffer compositions used in experiments, several isodesmic reactions involving chloride (Cl^-), hypophosphate (HPO<STACK>₄^2-</STACK>), and nitrosyl (NO) ligands are set up to find out whether the ligand-substituted products, which could have direct influence in CO releasing mechanism, are thermodynamically feasible. The isodesmic reactions involving the Cl^- and HPO<STACK>₄^2-</STACK> ligands are exothermic whereas it is endothermic with the NO ligand. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 [ABSTRACT FROM AUTHOR]