Structure of As-Se glasses by neutron diffraction with isotope substitution
| Autor: | Philip S. Salmon, Annalisa Polidori, Anita Zeidler |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Materials science
010304 chemical physics Isotope Coordination number Neutron diffraction Analytical chemistry General Physics and Astronomy chemistry.chemical_element Fraction (chemistry) 010402 general chemistry 01 natural sciences 0104 chemical sciences Isotopes of selenium Fragility chemistry Phase (matter) 0103 physical sciences Physical and Theoretical Chemistry Arsenic |
| Zdroj: | Polidori, A, Zeidler, A & Salmon, P 2020, ' Structure of As-Se glasses by neutron diffraction with isotope substitution ', Journal of Chemical Physics, vol. 153, no. 15, 154507 . https://doi.org/10.1063/5.0027171 |
| ISSN: | 1089-7690 |
| Popis: | The method of neutron diffraction with selenium isotope substitution is used to measure the structure of glassy As0.30Se0.70, As0.35Se0.65 and As0.40Se0.60. The method delivers three difference functions for each sample in which either the As-As, As-Se or Se-Se correlations are eliminated. The measured coordination numbers are consistent with the "8-N" rule and show that the As0.30Se0.70network is chemically ordered, a composition near to which there is a minimum in the fragility index and a boundary to the intermediate phase. Chemical ordering in glassy As0.35Se0.65 and As0.40Se0.60 is, however, broken by the appearance of As-As bonds, the fraction of which increases with the arsenic content of the glass. For the As0.40Se0.60 material, a substantial fraction of As-As and Se-Se defect pairs (~11%) is frozen into the network structure on glass formation. |
| Databáze: | OpenAIRE |
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