Synthesis, Crystal Structure, and Solid State NMR Spectroscopy of (C10N4H28)[Zn6(HPO4)2(PO4)4]·2H2O, a New Zinc Phosphate with a Layer Structure

✍ Scribed by Yung-Ping Chiang; Hsien-Ming Kao; Kwang-Hwa Lii

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 491 KB
• Volume: 162
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2001.9212

✦ Synopsis

A new zinc phosphate, (C 10 N 4 H 28 )[Zn 6 (HPO 4 ) 2 (PO 4 ) 4 ] ' 2H 2 O, with a layered architecture has been synthesized, for the 5rst time, in the presence of 1,4-bis(3-aminopropyl)piperazine as the structure-directing agent. The structure comprises a network of ZnO 4 and phosphate tetrahedra forming macroanionic layers with eight-membered apertures. Charge compensation is achieved by the quadruply protonated amine occupying interlamellar space and interacts with the inorganic layers via hydrogen bonding. The title compound is related to several other zinc phosphates in framework stoichiometry or crystal structure. Crystal data: (C 10 N 4 H 28 )[Zn 6 (HPO 4 ) 2 (PO 4 ) 4 ] ' 2H 2 O, triclinic, space group P1 (No. 2), a ‫؍‬ 8.3343(9) A s , b ‫؍‬ 12.413(1) A s , c ‫؍‬ 17.363(2) A s , ‫؍‬ 75.269(2)3, ‫؍‬ 78.868(2)3, ‫,3)2(072.67؍‬ V‫؍‬ 1670.7(5) A s 3 , Z ‫؍‬ 2, R 1 ‫؍‬ 0.0584, wR 2 ‫؍‬ 0.153. Proton-decoupled 31 P MAS NMR reveals six 31 P resonances with nearly equal intensities, which is in good agreement with the six distinct crystallographic phosphorus sites in the framework as indicated from X-ray structural analysis. 1 H P 31 P CP/MAS is used to obtain more details of the proximity between hydrogen and phosphorus atoms, and in combination with 2D RFDR NMR to assign the six phosphorus sites.