论文信息 - High-temperature calorimetry of (La1−xLnx)PO4 solid solutions

High-temperature calorimetry of (La1−xLnx)PO4 solid solutions

Abstract The enthalpy increment of the monazite-type solid solutions of LaPO 4 with NdPO 4 , EuPO 4 and GdPO 4 has been measured by drop calorimetry at T = 1000 K. The results show deviations (excess enthalpy) from ideal behaviour that have been interpreted in terms of lattice strains resulting from the ion size effects of substitution of La 3+ by Ln 3+ . For (La 0.5 Gd) 0.5 PO 4 also the temperature dependence has been determined for T = (515 to 1565) K, indicating that the excess enthalpy decreases with increasing temperature.

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