NaZnPO4 center dot 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), M(r) = 201.36 hexagonal, space group P6(1)22 (No. 178), a = 10.4797(8) Angstrom, c = 15.089(2) Angstrom, V = 1435 Angstrom(3), Z = 12, R = 5.99%, R(w) = 5.29% (709 observed reflections with I > 3 sigma(I). NaZnPO4 . H2O (II), M(r) = 201.36,hexagonal, space group P6(5)22 (No. 179), a = 10.412(2) Angstrom, c = 15.184(2) Angstrom, V = 1426 Angstrom(3), Z = 12, R = 6.90%, R(w) = 8.10% (687 observed reflections with I > 4 sigma(I).