Heterospin iron complexes with dioxolenes functionalized with stable radicals: quantum chemical study

A computational modeling (DFT UTPSSh/6-311++G(d,p)) of the electronic structures, energy characteristics, and magnetic properties of mononuclear iron complexes with tris-(2-pyridylmethyl)amine bases and dioxolenes bearing stable radicals (nitronyl nitroxyl, verdazyl, and dithiadiazolyl) was performed. Paramagnetism of all spin states of the molecules under study was predicted. The energy difference between the isomers of the studied complexes was found to be independent of the type of a radical substituent in the redox-active ligand but is controlled by varying the number of methyl groups in the ancillary N-donor base. The compounds potentially capable of exhibiting thermally initiated switching of spin states via the spin crossover mechanism were revealed.

Automated summary

The electronic structures, energy characteristics, and magnetic properties of mononuclear iron complexes with different stable radicals (nitronyl nitroxyl, verdazyl, and dithiadiazolyl) were investigated using computational modeling. It was found that the energy difference between isomers of the complexes is independent of the type of radical substituent, but is influenced by the number of methyl groups in the N-donor base. Compounds capable of thermally initiated spin state switching via spin crossover mechanism were identified.