A density functional theory study of multioxomolybdenum(VI) compounds [Mo2O6(imi)6] (imi = imidazole) and Mo2O6: Structure, bonding, and properties

Two dinuclear multioxomolybdenum(VI) compounds containing rare trans-configuration O-Mo-O groups, [Mo2O6(imi)4] (1) (imi = imidazole) and Mo2O6, have been investigated by the density functional theory level (DFT) calculation. The geometrical structure, electronic structure, and bonding properties of important Mo-ligand interactions (including Mo-O (terminal), Mo-O (bridging) and Mo-N (imi)) have been analyzed detailedly. Moreover, the influence of weak imi subgroup on the Mo2O6 core in 1 has been examined by the Mulliken population analysis (MPA), and the partial states of density (PDOS) and the overlap population density of states (OPDOS) analyses. The bond strength and covalency in them are in an order of Mo-O (terminal) > Mo-O (bridging) > Mo-N (imi). The introduction of imi ligand results in significant weakness of important Mo-ligand interactions, implying that the catalytic reactivity of such compounds in organic reactions can be suitably tuned by ligation of N-donor ligand to multioxomolybdenum(VI) core.