Czochralski growth, thermodynamic analysis and luminescent properties of Li2W1-xMoxO4 crystal material

• Published in: Journal of alloys and compounds 2021-01, Vol.850, p.156683, Article 156683
• Main Authors: Matskevich, N.I., Semerikova, A.N., Shlegel, V.N., Zaitsev, V.P., Matskevich, M.Yu, Anyfrieva, O.I.
• Format: Article
• Language: English
• Subjects: Anomalies; Calorimetry; Crystal growth; Crystal lattices; Czochralski method; Enthalpy; Heat capacity; Heat measurement; Low temperature; Luminescence; Optical properties; Oxide materials; Phase transitions; Single crystals; Specific heat; Stabilization
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2020.156683

High perfect single crystal of Li2W0·95Mo0·05O4, which is one of the perspective materials to search rare events, has been grown by a low-temperature-gradient Czochralski technique with weight control. Thermodynamics of obtained single crystal with emphasis on such basic characteristics as stabilization energy, lattice enthalpy, and standard formation enthalpy was studied using reaction calorimetry. It has been shown that dependences of lattice enthalpies and standard formation enthalpies on the molybdenum content (x) for Li2W1-xMoxO4 are linear. It has been established that stabilization energy of single crystal Li2W0·95Mo0·05O4 is several times more than stabilization energies of single crystals ZnMoO4 and CdWO4. The correlation was found between lattice energy of Li2W1-xMoxO4 compounds and luminescence wavelength. It was shown that for system Li2MoO4–Li2WO4, the luminescence wavelength is increased with increasing the lattice energy. The hypothesis to explain the correlation was formulated. The heat capacities for Li2MoO4 single crystal have been determined by DSC calorimetry in the temperature range of 303–819 K. No anomalies in heat capacities associated with phase transitions were found. [Display omitted] •High perfect single crystal of Li2W0·95Mo0·05O4 has been grown.•Linear dependences of lattice enthalpies and formation enthalpies on x for Li2W1-xMoxO4 have been found.•Li2W0·95Mo0·05O4 stabilization energy has been found several times more than ZnMoO4 and CdWO4 ones.•Luminescence wavelength in Li2MoO4–Li2WO4 has been found increased with increasing the lattice energy.•Heat capacities for Li2MoO4 single crystal have been determined in the temperature range of 303–819 K.