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

Abstract

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) Å, b = 6.9261(8) Å, c = 22.385(4)Å, β = 104.35(2)°, 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.