Synthesis and single-crystal structure of Cs3Zn4O(AsO4)(3)center dot 4H(2)O, an open-framework zinc arsenate

The synthesis and crystal structure of caesium zinc arsenate hydrate, Cs3Zn 4O(AsO4)(3) . 4H(2)O(3) are described. This open-framework zincoarsenate, w hich is built up from a three-dimensional network of vertex-sharing ZnO4 an d AsO4 tetrahedra, shows post-dehydration thermal stability to at least 600 degrees C. A model involving merohedral rotational twinning about [001] wa s required to arrive at a satisfactory single-crystal structure solution. C rystal data. Cs3Zn4O(AsO4)(3). 4H(2)O, M-r = 1165.05, tetragonal, space gro up P (4) over bar, (no. 81), a = 11.3099(2) Angstrom, c = 7.9216(2) Angstro m, V = 1013.28(4) Angstrom(3), Z = 2, R(F) = 3.90%, R-w(F) = 4.81% (740 ref lections with I > 3 sigma(I), 81 parameters). (C) 2000 Elsevier Science B.V . All rights reserved.