NaZnPO₄·H₂O, an Open-Framework Sodium Zincophosphate with a New Chiral Tetrahedral Framework Topology

Two approaches to the synthesis and structure determination of NaZnPO4·H2O, a new open-framework, chiral, hydrated sodium zincophosphate phase, are reported. The ordered, alternating, vertex-sharing ZnO4 and PO4 groups in NaZnPO4·H2O form a new framework topology, which includes novel 4-ring “squares” and edge-sharing helixes of 4-rings. The disordered extra-framework species (Na+, H2O) are located in pear-shaped cavities (12-ring diameter), interconnected through 8-rings and 6-rings. Crystal data: NaZnPO4·H2O (I), Mr = 201.36, hexagonal, space group P6122 (No. 178), a = 10.4797(8) Å, c = 15.089(2) Å, V = 1435 Å3, Z = 12, R = 5.99%, Rw = 5.29% (709 observed reflections with I > 3σ(I). NaZnPO4·H2O (II), Mr = 201.36, hexagonal, space group P6522 (No. 179), a = 10.412(2) Å, c = 15.184(2) Å, V = 1426 Å3, Z = 12, R = 6.90%, Rw = 8.10% (687 observed reflections with I > 4σ(I).本文报道了一种新型开放骨架手性含水磷酸锌钠物相NaZnPO₄·H₂O的两种合成与结构解析方法。该物相内有序交替、顶点共享的ZnO₄与PO₄四面体构成了全新的骨架拓扑结构，其中包含新颖的四元环“正方形”单元以及共边四元环螺旋链。骨架外的无序化学物种（Na⁺、H₂O）坐落于孔径为12元环的梨形空腔中，各空腔通过8元环与6元环相互连通。晶体学参数如下：物相I：NaZnPO₄·H₂O，相对分子质量Mᵣ=201.36，属六方晶系，空间群为P6₁22（编号178），晶胞参数a=10.4797(8) Å，c=15.089(2) Å，晶胞体积V=1435 ų，Z=12，残差因子R=5.99%，加权残差因子Rw=5.29%（基于709个衍射强度I>3σ(I)的观测衍射点）；物相II：NaZnPO₄·H₂O，相对分子质量Mᵣ=201.36，属六方晶系，空间群为P6₅22（编号179），晶胞参数a=10.412(2) Å，c=15.184(2) Å，晶胞体积V=1426 ų，Z=12，残差因子R=6.90%，加权残差因子Rw=8.10%（基于687个衍射强度I>4σ(I)的观测衍射点）。