Synthesis, structure and magnetic property of a new mixed-valence copper(I/II) complex derived from 3,5-bis(pyridin-2-yl)-1,2,4-triazole

A new mixed-valence copper(I,II) compound, [CuI2CuII(bpt)Cl3] (1), synthesized through solvothermal reaction of CuCl2·2H2O with 3,5-bis(pyridin-2-yl)-1,2,4-triazole (Hbpt) in methanol, has been characterized by X-ray crystallography, EPR and magnetism. Compound 1 crystallizes in the monoclinic space group P21/n with a=9.0743(12) Å, b=15.498(2) Å, c=10.5712(14) Å, β=90.693(2)°, V=1486.5(3) Å3, Z=4. The solid state EPR spectra of 1 at 8 K showed a typical axial spectrum with a four-line spectrum with hyperfine coupling constant (A) of 48 G. Magnetic susceptibility and magnetization measurements reveal that 1 is characteric of a mixed-valent CuI2CuII compound.