Crystal structure and ferrimagnetism of AgCo3Cr(MoO4)5 with mixed occupation of the transition metal sites

Abstract

We prepared a new compound, AgCo3Cr(MoO4)5, and characterized its crystal structure and physical properties. It crystallizes in the triclinic space group P1 @#x0305; with mixed occupations of the transition-metal sites M = (Co, Cr). The Ag site is split into three close positions. The magnetic subsystem of the title compound consists of M2O10 dimers and M3O14 trimers, made up of edge-sharing MO6 octahedra. These units are interconnected by MoO4 tetrahedra. Both ac and dc magnetic susceptibility, as well as specific heat and dielectric permittivity, evidence a ferrimagnetic behavior below at Tferri = 5.5 K. To investigate the properties of this nanostructured system, we evaluated the spin exchanges for the four most probable magnetic ion arrangements. We found that considering the local structure is essential for understanding the behavior of a magnet with mixed occupations of the transition metal sites.