Cobalt Borate Phosphate,Co_3[BPO_7], Synthesis and Characterization

摘要

Single crystals of Co_3[BPO_7] were obtained by boron flux method and characterized by single-crystal diffraction data. The compound crystallizes in the monoclinic space group Cm with a = 9.774(2), b = 12.688(2), c = 4.9057(8) A, 11 = 119.749(2)0; V = 528.20(15) A 3; Z = 4. The structure consists of Co in trigonal bipyramids, square pyramids, and distorted octahedra. Poly- hedral Co centers, triangular B centers, and tetrahedral P centers are joined together to form a three-dimensional network. The temperature dependence of the magnetic susceptibility of the compound follows the Curie-Weiss law to 30 K. Below this temperature, the magnetic behavior displayed first antifer- romagnetic ordering followed by ferrimagnetic coupling at 25 K.