Thermal Expansion and Luminescent Properties of Triorthogermanates CaLa_2-xEu_xGe₃O₁₀ (x = 0.0–0.6)

Solid solutions CaLa_2-xEu_xGe₃O₁₀ (x = 0.0–0.6, Δx = 0.1) have been synthesized for the first time. The compounds are isostructural to CaLa₂Ge₃O₁₀, they crystallize in the monoclinic system, space group P2₁/c, Z = 4. The low-temperature X-ray diffraction studies have revealed the strain anisotropy of germanate CaLa₂Ge₃O₁₀ crystal lattice in the temperature range 80–298 K, and the linear thermal expansion coefficients have been calculated. The optical properties of the activated phases have been studied, and the influence of the dopant concentration and the excitation wavelength on the luminescence characteristics of the synthesized compounds has been established.