Structure and bonding analysis of dimethylgallyl complexes of cobalt, rhodium and iridium [Me(PMe3)2(Me3GaCl)M(GaMe2)] (M = Co, Rh, Ir) and [Me(PMe3)2ClIr(GaMe2)]: A theoretical study

Electronic, molecular structures and bonding analysis of the terminal neutral dimethylgallyl complexes of cobalt, rhodium and iridium [Me(PMe3)2(Me3GaCl)M(GaMe2)] (M = Co, Rh, Ir) and [Me(PMe3)2ClIr(GaMe2)] were investigated at the DFT/BP86/TZ2P/ZORA level of theory. The calculated geometry of dimethylgallyl iridium complex [Me(PMe3)2(Me3GaCl)M(GaMe2)] is in excellent agreement with structurally characterized iridium complex. Mayer bond order of the optimized structures shows that the M–Ga bonds in these complexes are essentially M–Ga single bond, which is also supported by the performed energy decomposition analysis. The orbital interactions between the metal and gallium arise mainly from M ← GaMe2 σ donation. In all complexes, the π-bonding contribution is relatively smaller. The absolute values of the ΔEPauli, ΔEint and ΔEelstat contributions to the M–Ga bonds increase according to M = Co < Rh < Ir.