Monoclinic M‐orthotantalates of holmium and erbium ceramics were obtained by co‐precipitation and annealing at 1773 K and characterized by X‐ray powder diffraction, scanning electron microscopy, and chemical analysis. Using the high‐temperature X‐ray diffraction method, the temperature dependence of the monoclinic lattice parameters of both ceramics were determined at range 298‐1273 K. The molar heat capacity of M‐HoTaO₄ and M‐ErTaO₄ were measured by adiabatic (7‐350 K) and differential scanning (320‐1350 K) calorimetry. Standard thermodynamic function (entropy, enthalpy change, and reduced Gibbs energy) were calculated on the smoothed values of molar capacity, without taking into account contribution of low‐temperature interval: 0‐7 K for M‐HoTaO₄ and 0‐8 K for M‐ErTaO₄. The general shape of the anomalous Schottky contribution to the molar heat capacity was determined.

中文翻译：

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tan钽酸and和and陶瓷的热膨胀和热容

通过在1773 K下共沉淀和退火获得M和and陶瓷的单斜原钽酸钽，并通过X射线粉末衍射，扫描电子显微镜和化学分析对其进行表征。使用高温X射线衍射法，确定了两种陶瓷的单斜晶格参数与温度的关系，范围为298-1273K。M - HoTaO ₄和M- ErTaO ₄的摩尔热容通过绝热（73-350 K）和差示扫描（320-1350 K）量热法测量。根据摩尔容量的平滑值计算了标准热力学函数（熵，焓变和降低的吉布斯能量），而未考虑低温区间的影响：M- HoTaO ₄为0-7 K，M- HoTaO ₄为0-8 K M‐ ErTaO ₄。确定了反常的肖特基对摩尔热容的总体形状。