Theoretical studies on the spin exchange interaction in copper(II) complexes coordinated with nitronyl nitroxide

Nitronyl nitroxide radical 1, NIT (4, 4, 5, 5-tetramethyl-4, 5-dihydro-1H-imidazolyl-loxyl-3-oxide) and copper(II) chloride complexes with nitronyl nitroxide 2, [Cu(NITPh)(2)Cl-2] (NITPh = 2-phenyl-4, 4, 5, 5 -tetramethyl-imidazoline-1-oxyl-3-oxide) were studied with density functional theory (DFT). The magnetic orbital analysis reveals that the antiferromagnetic coupling for complex 2 is due to the antibonding sigma*-orbital overlap between d(x2-y2) (Cu) and pi* (NO) orbitals. Also, spin population and atomic charge distribution analysis suggest that for AFS of complex 2 the antiferromagnetic coupling between the radical ligands and the copper(II) ion originates from the spin delocalization induced by the alpha electron transfer from pi*(NO) to d(x2-y2) (Cu) orbital.Chemistry, MultidisciplinarySCI(E)中国科技核心期刊(ISTIC)0ARTICLE121313-13161