Dual magnetic behavior of Co(II) and Fe(II) bis(chelate) adducts with Di-o-diiminobenzoquinone: Quantum chemical modeling

Abstract

Computational modeling (DFT UB3LYP*/6-311++G(d,p)) of electroneutral binuclear 2: 1 adducts of cobalt and iron bis(chelates) with N-phenyl-di-o-diiminobenzoquinone bearing the dimethylene linker is performed. The geometries of all electromers of the complexes are determined, and their stabilization energies and exchange interaction parameters are calculated. The magnetic properties of the compounds under study are determined by the metal nature: the cobalt diketonate adducts undergo one- and two-step valence tautomeric rearrangements, while the mixed-ligand iron complexes are capable of demonstrating spin crossover. The calculation results make it possible to regard the studied adducts as the basis for designing molecular switches and spin qubits.