Synthesis, Single-Crystal Structure, Dielectric Properties of a New Phosphate K3Bi6.5(PO4)7.5

New potassium bismuth phosphate K3Bi6.5(PO4)(7.5) has been synthesized by solid-state reaction and characterized by single-crystal X-ray diffraction. This compound crystallizes in the monoclinic system, space group C2, with a = 17.637(8) angstrom, b = 6.9261(8) angstrom, c = 22.385(4)angstrom, beta = 104.35(2)degrees, and Z = 4. The crystal structure model is supported by the two methods; the charge distribution (CHARDI) and bond valence sum (BVS). The crystal structure is made up of BiOn (n = 5, 6, 7, 8) polyhedra and PO4 tetrahedra sharing corners and edges to form a three-dimensional anionic framework. The bond valence sum energy (BVSE) model of simulation shows that the potassium atoms move along [101] direction with a zigzag pathways form with an empirical activation energy of about 1.56 eV. The dielectric properties are carried out at room temperature and show high permittivity values with low dielectric loss.