SU-12: A Silicon-Substituted ASU-16 with Circular 24-Rings and Templated by a Monoamine
Autor: | Liqiu Tang, Xiaodong Zou, Mike S. Dadachov |
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Rok vydání: | 2005 |
Předmět: |
Diffraction
Materials science Silicon General Chemical Engineering chemistry.chemical_element General Medicine General Chemistry Tetragonal crystal system Crystallography Monoamine neurotransmitter chemistry Group (periodic table) Materials Chemistry Organic chemistry Orthorhombic crystal system Germanate Symmetry (geometry) Science technology and society |
Zdroj: | Chemistry of Materials. 17:2530-2536 |
ISSN: | 1520-5002 0897-4756 |
DOI: | 10.1021/cm049373f |
Popis: | A new silicogermanate, SU-12, |(CH3CH2CH2NH3)3(H2O)2.5|[(Ge6.44Si0.56)O14.5F2], with 24-ring channel systems was synthesized under hydro/solvothermal conditions, and its structure was determined by single-crystal X-ray diffraction. It is the first silicogermanate with extra-large 24-rings templated by a primary monoamine. Crystallographic data: tetragonal, space group I42m, unit cell parameters a = 27.6460(22) A and c = 17.0885(14) A, V = 13060.8(17) A3, Z = 16, ρcalcd = 1.797 g/cm3, R1 = 0.0512 [5471 observed reflections with I > 2σ(I)], wR2 = 0.1487, S (goodness-of-fit on F2) = 1.08. SU-12 has a structure topology similar to that of the pure germanate ASU-16. However, the symmetry of SU-12 is higher than that of ASU-16, and the 24-rings become more circular than those in ASU-16. The interaction between the templates and framework is compared for ASU-16 and SU-12, and their thermal stabilities are studied. The orthorhombic ASU-16 is thermally less stable than the tetragonal SU-12 and transformed to SU-... |
Databáze: | OpenAIRE |
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