Computer Simulation of the Structure and Magnetic Properties of Cobalt Complexes with N-Substituted Pyridinophanes and Radical-Functionalized o-Benzoquinones

Abstract

The structure and energy and magnetic characteristics of mononuclear cobalt complex with N,N'-dialkyl-2,11-diaza[3.3]-(2,6)pyridinophanes and o-benzoquinone ligands containing stable radicals (nitronyl nitroxide and TEMPO) were studied by the density functional theory (DFT UTPSSh/6-311++G(d,p)). It was shown that the stability of electromeric forms of complexes and, hence, the possibility of implementing the magnetic bistability mechanisms (spin-crossover and valence tautomerism) can be controlled by varying alkyl substituents at the tetraazamacrocycle nitrogen atoms. The nature of the radical group determines the strength of exchange interactions in which it participates, but does not affect the exchange in the redox-active moiety.