Синтез, выращивание и структурные свойства твердых растворов (Cu1-xAgx)7GeSe5I
| Jazyk: | ukrajinština |
|---|---|
| Rok vydání: | 2019 |
| Předmět: | |
| Zdroj: | Scientific Herald of Uzhhorod University.Series Physics; Том 45 (2019); 7-13 Научный вестник Ужгородского университета. Серия Физика; Том 45 (2019); 7-13 Науковий вісник Ужгородського університету. Серія Фізика; Том 45 (2019); 7-13 |
| ISSN: | 2415-8038 |
| Popis: | Проведено синтез та вирощування монокристалів твердих розчинів (Cu1-xAgx)7GeSe5I. Рентгеноструктурні дослідження показали, що у системі Cu7GeSe5I – Ag7GeSe5I утворюється неперервний ряд твердих розчинів (Cu1-xAgx)7GeSe5I, які кристалізуються в гранецентрованiй кубiчнiй комiрцi . Встановлено, що концентраційна зміна параметра гратки відбувається у відповідності до закону Вегарда. Проведены синтез и выращивание монокристаллов твердых растворов (Cu1-xAgx)7GeSe5I. Рентгеноструктурные исследования показали, что в системе Cu7GeSe5I – Ag7GeSe5I образуется непрерывний ряд твердых растворов (Cu1-xAgx)7GeSe5I, которые кристаллизуются в гранецентрированной кубической ячейке . Показано, что концентрационное изменение параметра решетки происходит в соответствии с законом Вегарда. Purpose. The purpose of this work was synthesis and crystal growth, X-ray diffraction studies, investigating the compositionalbehavior of the lattice parameter and the density of (Cu1−xAgx)7GeSe5I solid solutions.Methods. Single crystals of quaternary compounds with argyrodite structure Cu7GeSe5I, Ag7GeSe5I and solid solutionson their basis (Cu1−xAgx)7GeSe5I with x = 0; 0.25; 0.5; 0.75; 1 were grown by direct crystallization(Cu7GeSe5I, Ag7GeSe5I) and zone crystallization ((Cu1−xAgx)7GeSe5I) from the melt using a modified method.Structural studies were carried out by the methods of differential thermal analysis (chromel-alumel thermocouples,heating and cooling speed 700 K/h) and X-ray phase analysis (DRON 4-07, CuKα radiation, scan angle speed 2Θ –0.02 deg, exposure – 1 s).Results. In order to establish near-optimal technological regimes for the growth of single crystals as both individualcompounds of Cu7GeSe5I та Ag7GeSe5I, and solid solutions on their basis (Cu1−xAgx)7GeSe5I they were investigatedby the method of differential thermal analysis. The diffraction patterns of Cu7GeSe5I and Ag7GeSe5I compoundsare indexed in a face-centered cubic lattice. The number and nature of the reflexes on diffractograms of solid solutionsindicate that a continuous series of solid solutions is formed in the system. The compositional dependence of the latticeparameter was constructed, which is described by Vegard law. As the content of silver increases, a linear increase inthe cubic lattice parameter and a nonlinear increase in density are observed.Conclusions. Synthesis and growth of single crystals of (Cu1−xAgx)7GeSe5I solid solutions was performed. Thegrowth was carried out by the methods of direct crystallization (Cu7GeSe5I, Ag7GeSe5I) and zone crystallization(Cu1−xAgx)7GeSe5I from the melt using a modified method. According to the results of X-ray diffraction studies, it isestablished that in Cu7GeSe5I – Ag7GeSe5I system a continuous series of solid solutions is formed. The compositionaldependences of the lattice parameter and density are constructed. It was found out that with increasing silver content, alinear increase in the cubic lattice parameter and a nonlinear increase in density in (Cu1−xAgx)7GeSe5I solid solutionsare observed. |
| Databáze: | OpenAIRE |
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