(GeTe)nSbInTe3 (n≤3)—Element distribution and thermal behavior
| Autor: | Oliver Oeckler, Philipp Urban, Thorsten Schröder, Felix Fahrnbauer, Tobias Rosenthal, Simon Welzmiller |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Materials science
Anomalous scattering Mineralogy chemistry.chemical_element Germanium Condensed Matter Physics Electronic Optical and Magnetic Materials Inorganic Chemistry Crystallography symbols.namesake chemistry Antimony X-ray crystallography Materials Chemistry Ceramics and Composites symbols Lamellar structure Physical and Theoretical Chemistry van der Waals force Ternary operation Powder diffraction |
| Zdroj: | Journal of Solid State Chemistry. 208:20-26 |
| ISSN: | 0022-4596 |
| Popis: | Antimony in germanium antimony tellurides (GeTe)n(Sb2Te3) can be substituted by indium. Homogeneous bulk samples of GeSbInTe4 (R3m, Z=3, a=4.21324(5) A, c=41.0348(10) A) and Ge2SbInTe5 (P3m1, Z=1, a=4.20204(6) A, c=17.2076(4) A) were obtained; their structures were refined with the Rietveld method. Single-crystal X-ray diffraction using synchrotron radiation at the K edges of Sb and Te (exploiting anomalous dispersion) yields precise information on the element distribution in the trigonal layered structure of Ge3SbInTe6 (R3m, Z=3, a=4.19789(4) A, c=62.1620(11) A). The structure is characterized by van der Waals gaps between distorted rocksalt-type slabs of alternating cation and anion layers. The cation concentration is commensurately modulated with Sb preferring the positions near the gaps. In contrast to unsubstituted Ge3Sb2Te6, quenching the NaCl-type high-temperature phase (stable above ~510 °C) easily yields a pseudocubic modification that is metastable at ambient conditions. Temperature-dependent powder diffraction reveals a broader stability range of the cubic high-temperature modification of Ge3SbInTe6 compared to the ternary phases. In-containing samples partially decompose at ca. 300 °C but become homogeneous again when the high-temperature phase is formed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect