Thermodynamics of Na3Cr2(AsO4)3 with garnet structure

• Published in: The Journal of chemical thermodynamics Vol. 200; p. 107364
• Main Authors: Smirnova, Natalia N., Piaterikov, Egor A., Pet’kov, Vladimir I., Shotina, Valeria A., Markin, Alexey V.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-01-2025
• Subjects: Garnet; Heat capacity; Na3Cr2(AsO4)3; Precise adiabatic calorimetry; Standard thermodynamic functions; Heat capacity; Standard thermodynamic functions; Garnet; Na3Cr2(AsO4)3; Precise adiabatic calorimetry
• ISSN: 0021-9614
• DOI: 10.1016/j.jct.2024.107364

[Display omitted]
•Na3Cr2(AsO4)3 compound of garnet structure was synthesized via co-deposition method.•Structural characteristics were obtained by XRD, IR, microprobe analysis.•Heat capacity and thermodynamic functions between T→0 and 323 K were investigated.•Exothermic effect around 20 K was detected and explained.
In this work the heat capacity Cp,mo=f(T) of the garnet-structured Na3Cr2(AsO4)3 was first investigated. Measurements were performed in the range of T = (5 and 323) K using a precise adiabatic vacuum calorimeter. The phase purity and composition homogeneity were verified by X-ray diffraction analysis with Rietveld method calculations and X-ray microanalysis. The Cp,mo,Δ0THm0,Δ0TSm0andΔ0TGm0 have been calculated using experimental data from T→0 to 323 K.