Crystal structure, Hirshfeld surface, novel XPS spectroscopy and magnetic properties of a hybrid solid with tetrahedral coordination sphere tetrabromocuprate (II)

Abstract

The synthesis and physico-chemical characterization of an organic-inorganic hybrid material, (N, N'-bi-n-butyl-4,4′-bipyridinium tetrabromocuprate, has been reported. This hybrid has been characterized using IR, thermogravimetric and single-crystal X-ray diffraction analyses. In the title salt, (C18H26N2)[CuBr4], the CuBr42− ion shows distorted tetrahedral geometry. The tetrabromocuprate and N, N'-bi-n-butyl-4,4′-bipyridiniums are held together via non-classical CH⋯Br hydrogen bond to form a 3-D hybrid structure. The percentages of hydrogen bonding interactions are analyzed by fingerprint plots of Hirshfeld surface. The XPS spectrum exhibits the signals of coexistence of CuI and CuII ions. However, the hybrid shows EPR silent behavior at room temperature and variable-temperature magnetic susceptibility displays an isolation of CuII feature with C=0.46emuK mol−1 and θ approximate to −0.06K in 2–K as well. Such a novel nature is further analyzed and discussed.