Preparation and Crystal Structure of Na2Zn(HPO4)2 · 4H2O, a New Layered Sodium Zinc Phosphate Containing "Bifurcated" Tetrahedral 12-Rings

✍ Scribed by William T.A. Harrison; Tina M. Nenoff; Thurman E. Gier; Galen D. Stucky

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 358 KB
• Volume: 113
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1994.1356

✦ Synopsis

We report the low-temperature (\left(\sim 0^{\circ} \mathrm{C}\right)) synthesis and (\mathrm{X})-ray single-crystal structure of (\mathrm{Na}{2} \mathrm{Zn}\left(\mathrm{HPO}{4}\right) \cdot 4!\mathrm{I}{2} \mathrm{O}), a new layered material, whose structure is built up from sheets of vertex-sharing (\mathrm{ZnO}{4}) and (\mathrm{HPO}{4}) tetrahedra, which encapsulate octahedrally coordinated "guest" sodium cations and water molecules. The (\mathrm{Zn} / \mathrm{P}) tetrahedral-atom connectivity in (\mathrm{Na}{2} \mathrm{Zn}\left(\mathrm{HPO}{4}\right){2} \cdot 4 \mathrm{H}{2} \mathrm{O}) results in a twodimensional network of layers of "bifurcated," tetrahedral 12rings, with interlayer connectivity established only by sodium cations and via (\mathrm{H}) bonds. (\mathrm{X})-ray powder data and ({ }^{3!} \mathrm{P}) MAS NMR spectra are consistent with those expected from the crystal structure data. Crystal data are (\mathrm{Na}{2} \mathrm{Zn}\left(\mathrm{HPO}{4}\right){2} \cdot \mathbf{4 H}{2} \mathrm{O}\left(\mathrm{ZnNa}{2} \mathrm{P}{2} \mathrm{O}{12} \mathrm{H}{10}\right)), (M{\mathrm{r}}=375.37), monoclinic, space group (P 2_{1} / c) (No. 14), (a=8.947) (2) (\AA, b=13.254(2) \AA, c=10.098(2) \AA, \beta=116.358(6)^{\circ}, V=1074.5) (\AA^{3}, Z=4, R=4.25 %), and (R_{\mathrm{w}}=5.68 %) [ 1608 unique reflections with (I>3 \sigma(I)]). O 1994 Academic Press, Inc.