| Автор | M V Gorev |
| Автор | I N Flerov |
| Автор | A Tressaud |
| Дата выпуска | 1999-10-04 |
| dc.description | Calorimetric and high pressure experiments are used to establish thermodynamic features of (NH<sub>4</sub>)<sub>3</sub>M<sup>3+</sup>F<sub>6</sub> cryolites with M<sup>3+</sup>: Ga, Sc as they undergo one and three structural phase transitions, respectively. The heat capacity measurements performed between 80 K and 370 K, using an adiabatic calorimeter, have shown that all phase transitions under study are first order with different closeness to the tricritical point. The total entropy change in the Sc compound connected with the successive transformations is almost equal to the entropy change in the Ga cryolite. The effect of hydrostatic pressure has been studied up to 0.6 GPa, using differential thermographic analysis. The p-T phase diagrams of both cryolites were found to be rather complicated, including triple points. The experimental results are considered as connected with order-disorder phase transitions. |
| Формат | application.pdf |
| Издатель | Institute of Physics Publishing |
| Название | Thermodynamic properties and p-T phase diagrams of (NH<sub>4</sub>)<sub>3</sub>M<sup>3+</sup>F<sub>6</sub> cryolites (M<sup>3+</sup>: Ga, Sc) |
| Тип | paper |
| DOI | 10.1088/0953-8984/11/39/306 |
| Electronic ISSN | 1361-648X |
| Print ISSN | 0953-8984 |
| Журнал | Journal of Physics: Condensed Matter |
| Том | 11 |
| Первая страница | 7493 |
| Последняя страница | 7500 |
| Выпуск | 39 |
