Thermal and electrical properties of Ca5Mg4−xZnx(VO4)6 (0 ≤ x ≤ 4)
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Calcium vanadates Ca5Mg4−xZnx(VO4)6 (0 ≤ x ≤ 4) have been studied for the first time using a set of high-temperature methods of analysis. The onset of melting process determined from differential scanning calorimetry decreases from 1158 to 881 °C (± 1.5 °C) with increasing of x (dopant’s content). CTE temperature dependence is found to show a hysteresis. Electrical transport properties measured by impedance spectroscopy in air of different humidity are also discussed. The value of electrical conductivity does not depend on air humidity. It is found to equal to 1.5 × 10−6 S cm−1 at 720 °C for Ca5Mg4(VO4)6 which is specific for garnet-related crystals.
KeywordsNon-stoichiometric garnet Electrical conductivity DSC Thermal expansion
The reported study was funded by the RFBR according to the research Project No. 17–03–01280. Powder diffraction experiments were carried out in the Shared Access Centre at the IHTE UB RAS.
- 8.Gfeller F. Mayenite Ca12Al14O32[X2−]: from minerals to the first stable electride crystals: highlights in mineralogical crystallography/Thomas Armbruster; Rosa Micaela Danisi. Berlin: de Gruyter; 2016.Google Scholar
- 11.Lide DR, editor. CRC handbook of chemistry and physics. 84th ed. Boca Raton: CRC Press; 2003. p. 4–93.Google Scholar
- 12.Dhar R, Pandey RS, Srivastava SL. Applicability of Van’t Hoff equation in calculation of impurities in liquid crystalline materials. Indian J Pure Appl Phys. 2002;40:42–4.Google Scholar