In situ high-pressure X-ray diffraction study of densification of a molecular chalcogenide glass
Journal of Physics and Chemistry of Solids, cilt.69, sa.9, ss.2336-2340, 2008 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 69 Sayı: 9
- Basım Tarihi: 2008
- Doi Numarası: 10.1016/j.jpcs.2008.04.004
- Dergi Adı: Journal of Physics and Chemistry of Solids
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.2336-2340
- Anahtar Kelimeler: A. Glasses, A. Non-crystalline materials, C. High pressure, C. X-ray diffraction, D. Phase transitions
- Boğaziçi Üniversitesi Adresli: Hayır
Özet
Structural mechanisms of densification of a molecular chalcogenide glass of composition Ge2.5As51.25S46.25 have been studied in situ at pressures ranging from 1 atm to 11 GPa at ambient temperature as well as ex situ on a sample quenched from 12 GPa and ambient temperature using high-energy X-ray diffraction. The X-ray structure factors display a reduction in height of the first sharp diffraction peak and a growth of the principal diffraction peak with a concomitant shift to higher Q-values with increasing pressure. At low pressures of at least up to 5 GPa the densification of the structure primarily involves an increase in the packing of the As4S3 molecules. At higher pressures the As4S3 molecules break up and reconnect to form a high-density network with increased extended-range ordering at the highest pressure of 11 GPa indicating a structural transition. This high-density network structure relaxes only slightly on decompression indicating that the pressure-induced structural changes are quenchable. © 2008 Elsevier Ltd.