Synthesis, X-ray analysis, and quantum-chemical DFT study of features in formation of a binuclear phenanthroline complex with a VIV-O-VV core

A new mixed-valence complex [(O)(phen)(2)V-IV(mu-O)V-V(O)phen)(mal)](+) was synthesized and characterized by the X-ray structural analysis. Its geometric structure was simulated by the DFT M06/6-31G(d,p) method. Comparison of calculated and experimental data made it possible to draw a conclusion on the oxobridging nature of the bond between vanadium fragments and to confirm the value of the target compound charge. The energy characteristics of cation formation reactions in solution were estimated. It was found that the oxidation of V-IV to V-V assists subsequent substitution of ligands. Joining [(O)V-IV(phen)(2)](2+) and [(O)V-V(O)(phen)(mal)](-) particles proceeds by the donor-acceptor mechanism.