2001 structure

structure (solids and liquids)D 2000

40 - 011Ab initio Structure Determination of a Small-Pore FrameworkSodium Stannosilicate. — Na2SnSi3O9·2H2O is prepared hydrothermallyfrom a gel containing Na2SiO3·5H2O, SnCl4·5H2O, NaOH, NaCl, H2O (1.autoclave, 200 ◦C, 4 d; 2. addn. of NaOH, 200 ◦C, 5 d). The structureof the compound is studied by powder XRD, SEM, 29Si, 119Sn, single andtriple quantum 23Na MAS NMR, and TG. Na2SnSi3O9·2H2O crystallizes inthe orthorhombic space group C2221 with Z = 4. The structure consists ofa three-dimensional framework of corner-sharing SnO6 octahedra and SiO4

tetrahedra. The SiO4 tetrahedra form helix chains which are interconnected bythe SnO6 octahedra. There are no Sn–O–Sn linkages in the framework. —(FERREIRA, ARTUR; LIN, ZHI; ROCHA, JOAO; MORAIS, CLAUDIA M.;LOPES, MARTA; FERNANDEZ, CHRISTIAN; Inorg. Chem. 40 (2001) 14,3330-3335; Dep. Chem., Univ. Aveiro, P-3810 Aveiro, Port.; EN)

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