Synthesis, crystal growth and characterization of a new noncentrosymmetric borophosphate: RbPbBP2O8

Abstract

A new noncentrosymmetric borophosphate, RbPbBP₂O₈, has been synthesized and its high quality single crystal with dimensions up to 23 mm × 18 mm × 7 mm was successfully grown by the Kyropoulos method for the first time. It crystallizes in the tetragonal system, space group I2d with cell parameters a = 7.213(3) Å, c = 13.987(10) Å, Z = 4, V = 727.8(6) ų. The structure analysis reveals that RbPbBP₂O₈ features a three-dimensional framework composed of BO₄ and PO₄ tetrahedra interconnected by MO₈ (M = Rb/Pb) distorted polyhedra. The powder second harmonic generation effect of RbPbBP₂O₈ is similar to that of KH₂PO₄. Thermal analysis and transmittance spectroscopy were also performed on the reported crystal.