Material properties of nonstoichiometric solids

作者：Sedmidubsky David^*; Holba Pavel

来源：Journal of Thermal Analysis and Calorimetry, 2015, 120(1): 183-188.

DOI：10.1007/s10973-015-4466-7

• Nonstoichiometry
• Controlled atmosphere
• Heat capacity
• Thermal expansion
• Compressibility

Following our recently reported theoretical description of heat capacity of nonstoichiometric solids published in this journal, we extended this approach based on redefining the heat capacity conventionally valid for isoplethal conditions (fixed content of all components) to isodynamical conditions (controlled activity of a component shared with surroundings) and formulated a similar ansatz for other material characteristics such as thermal expansion and isothermal compressibility. As for the heat capacity, two additional terms are identified: the saturation contribution due to incorporation (or release) of the free component and the contribution due to deviation from stoichiometry. Involving some newly defined quantities reflecting the variation of stoichiometry with temperature, pressure, and activity, the resulting equations provide a direct link to experiment.

• 出版日期2015-4