Energy decomposition analysis and natural orbital for chemical valence of complexes with n-heterocyclic carbene and analogues

Abstract

The natural of W-E bonding in group I4 compounds [(CO)jW-{NHE}] (W4-NHE) has been investigated by means of the Energy Decomposition Analysis-Natural Orbital for Chemical Valence (EDA-NOCV) method W'hich combines charge (NOCV) and energy (EDA) partitioning schemes at the BP86/TZ2P-t- level of theory. The EDA-NOCV results indicate that the decrease in bond strength from W4-NHC to W4-NHPb correlates with the decrease of and AEgrh and the trend of the W-E bond strength was W4-NHC > W4-NHS1 > W4-NHGe > W4-NHSn > W4-NHPb. The decrease in the donation (CO)a^<— NHE, which is manifested in the calculated values for AEtj and in the electrostatic attraction , provides a rationale for the weaker bonding of the heavier atoms E. The bonding in the complexes with N-helerocyclic carbene and analogues W4-NHE exhibits the typical feature in terms of strong c-donation and weak K- donation. All investigated complexes [(CO)4W-{NHE}] are suitable targets for synthesis which will open the door to a new field of experimental chemistry.