LAUSR

Abstract The magnetically-active dinuclear metal complexes with previously unstudied di-o-quinone ligands comprising paramagnetic acene linkers have been investigated with the use of density functional theory quantum-chemical calculations (UTPSSh/UB3LYP/6-311++G(d,p)). Two types of linker groups are considered: linear acenes comprising various number of six-membered cycles and polycyclic hydrocarbons containing terminal five-membered rings. In sodium complexes replacement of terminal six-atomic hydrocarbon rings of the acene chain by five-membered cycles results in changing the type of the exchange interactions involving o-semiquinone radical-anions from antiferromagnetic to ferromagnetic. All paramagnetic centers in copper complexes with dicatecholate forms of the redox-active ligands are antiferromagnetically coupled. The performed computational modeling has shown that the nature and strength of the exchange interactions between paramagnetic centers of the compounds under study depend on the structure of the polycyclic hydrocarbon determined by the type of terminal rings and oxidation state of the redox-active moieties.