Low-temperature flux syntheses and characterizations of two 1-D anhydrous borophosphates: Na3B6PO13 and Na3BP2O8

摘要

Two new anhydrous sodium borophosphates with one-dimensional structure, Na3B6PO13 (1) and Na3BP2O8 (2), were synthesized by low-temperature inolten salts techniques using boric acid and sodium dihydrogen phosphate as flux, respectively. The crystal structures were solved by means of single-crystal X-ray diffraction (1, orthorhombic, Pnma (no. 62), a = 9.3727(4) angstrom, b = 16.2307(7) angstrom, c = 6.7232(3) angstrom, Z = 4; 2, monoclinic, C2/c (no. 15), a = 12.567(4) angstrom, b = 10.290(3) angstrom, c = 10.210(3) angstrom, beta = 92.492(5)degrees, Z = 8). Compound 1 is characterized by an infinite chain of (1)(infinity){[B6PO13]}(3-) containing eight-membered rings in which all vertexes of borate groups contribute to interconnection. Compound 2 reveals an infinite straight chain (1)(infinity){[BP2O8]}(3-) built of vertex-sharing four-membered rings, and chains in neighboring layers arranged along different orientations. The relations between structures and the synthetic conditions with only traced water are discussed. (c) 2006 Elsevier Inc. All rights reserved.