ZnBPO4(OH)(2): A zinc borophosphate with the rare moganite-type topology

摘要

A novel zinc borophosphate ZnBPO4(OH)(2) with moganite-type topology (a rare polymorph of silica) has been prepared from a mixture of ZnO, B2O3, and P2O5 by hydrothermal treatment at 443 K. The crystal structure was determined from single-crystal X-ray data (orthorhombic, Pbcn (no. 60), a=915.07(3), b=897.22(3), c=1059.19(3) pm, V=869.62(5) x 10(6) pm(3), Z=8, R1=0.028, wR2=0.075). The crystal structure comprises unbranched vierer-single borophosphate chains running along 0101 and interconnected via ZnO2(OH)(2)-tetrahedra by sharing common vertices. The resulting topology of the three-dimensional tetrahedral framework structure is described by the Schlafli symbol (4(2).6(2).8(2)) (4.6(4).8)(2). Although showing Zn in a tetrahedral coordination, the title compound does not belong to the group of zincoborophosphates but is a special case of a borophosphate containing vierer single rings of tetrahedra with the sequence Zn-B-Zn-P.