Ca2−xLi2xGeO4 solid solutions. Chemical composition range and flux crystal growth

Abstract A series of Ca 2−x Li 2x GeO 4 specimens with 0  2−x Li 2x GeO 4 solid solutions of Ca 2 GeO 4 structure crystallized. The cell parameters of these solid solutions linearly decreased upon increasing the lithium concentration, which means that the solutions are in accordance with the Vegard's law. For 2x > 0.6 the specimens contained two phases: (i) Ca 2−x Li 2x GeO 4 solid solutions with maximum lithium concentration approximately equal to that for 2x = 0.6 and minimum values of the cell parameters and (ii) Li 2 CaGeO 4 phase. Li 2 O·MoO 3 –Ca 2 GeO 4 high-temperature solutions were used to grow Ca 2−x Li 2x GeO 4 solid solutions and Li 2 CaGeO 4 single crystals by the high temperature solution (flux) method. Li 2 CaGeO 4 crystals were grown in the concentration range 8–26 wt. % Ca 2 GeO 4 in the temperature range 830–980 °C. Crystals with chemical compositions of the Ca 2−x Li 2x GeO 4 solid solutions with different Li concentrations were grown in the concentration range 26–40 wt. % Ca 2 GeO 4 in the temperature range 980–1090 °C.