Ag9I3(SeO4)2(IO3)2- Synthesis, Crystal Structure, and Ionic Conductivity

Autor: Jan Curda, Dragan Pitzschke, Martin Jansen, Gueliz Cakmak
Rok vydání: 2008
Předmět:
Zdroj: Zeitschrift für anorganische und allgemeine Chemie. 634:1907-1910
ISSN: 1521-3749
0044-2313
DOI: 10.1002/zaac.200800258
Popis: Ag9I3(SeO4)2(IO3)2 was obtained for the first time by reacting a stoichiometric mixture of Ag2O, AgI and SeO2 at elevated oxygen pressure (255 MPa) and at a temperature of 500 °C. Ag9I3(SeO4)2(IO3)2 was characterized by X-ray powder diffraction, differential scanning calorimetry, impedance spectroscopy and single crystal structure analysis. The crystal structure was solved by direct methods (I23, Z = 8, a = 12.9584(6) A, V = 2175.9(2) A3 and R1 = 2.70 %). The crystal structure consists of isolated SeO4 tetrahedra and trigonal IO3 pyramids separated by Ag+ and I– ions. Each four of the SeO42– and IO3– anions aggregate, forming a novel supramolecular building block, showing a hetero-cubane like structure. According to the results of impedance measurements, Ag9I3(SeO4)2(IO3)2 is a good silver ion conductor. The compound shows an abrupt increase in the ionic conductivity in the temperature range of 115 to 147 °C, and has a silver ion conductivity of 7.1 × 10–5 Ω–1 cm–1 at 25 °C. The activation energy for silver ion conduction is 0.45 eV, in the temperature range from 25 to 115°.
Databáze: OpenAIRE
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