Structure and bonding analysis of dimethylgallyl complexes of cobalt, rhodium and iridium [Me(PMe _3) _2(Me _3GaCl) M(GaMe _2)] (M = Co, Rh, Ir) and [Me(PMe _3) _2ClIr(GaMe _2)]: A theoretical study

摘要

Electronic, molecular structures and bonding analysis of the terminal neutral dimethylgallyl complexes of cobalt, rhodium and iridium [Me(PMe _3) _2(Me _3GaCl)M(GaMe _2)] (M = Co, Rh, Ir) and [Me(PMe _3) _2ClIr(GaMe _2)] were investigated at the DFT/BP86/TZ2P/ZORA level of theory. The calculated geometry of dimethylgallyl iridium complex [Me(PMe _3) _2(Me _3GaCl)M(GaMe _2)] 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 ← GaMe _2 σ donation. In all complexes, the π-bonding contribution is relatively smaller. The absolute values of the ΔE _(Pauli), ΔE _(int) and ΔE _(elstat) contributions to the M-Ga bonds increase according to M = Co < Rh < Ir.