Computational modeling of structure and magnetic properties of dinuclear di-o-benzoquinone iron complexes with linear polycyclic linkers

Density functional theory (DFT UTPSSh/6-311++G(d,p)) quantum chemical modeling of geometry, energy and magnetic characteristics of binuclear iron complexes, in which iron atoms coordinated by 2,11-diaza[3.3](2,6)pyridinophane bases are connected by di-o-benzoquinone ligands with acene linkers, was performed. It is established that the energy diff erence between electromeric forms of the studied compounds is determined by the type of the alkyl substituents at the nitrogen atoms of the tetraazamacrocyclic ligand and does not depend on the structure of the polycyclic chain. The possibility of controlling magnetic properties of the molecules of this type by means of external influences is predicted based on the facts that terminal metal-containing fragments are capable of undergoing thermally induced spin-state switching rearrangements, while the singlet-triplet transition of the acene linker can be induced by light irradiation.