@article{12369b8b574245ec88dae2d18e4e48e4,
title = "Structural and thermodynamic mixing properties of La1−xNdxPO4 monazite-type solid solutions",
abstract = "La1−xNdxPO4 monazite-type ceramics were synthesized by precipitation and sintering. The obtained crystalline powders and pellets were structurally characterized by X-ray diffraction, electron microscopy, and infrared and Raman spectroscopy. The determined unit cell constants agree with published values for the pure end-members ranging from LaPO4 to DyPO4, as well as with values for known mixed monazite-type lanthanide orthophosphates, indicating a homogeneous solid solution. However, Raman spectroscopy shows a change in short-range order and the results of high temperature oxide melt solution calorimetry suggest a subregular solid solution, which requires two Margules parameters to calculate the observed enthalpy of mixing ΔHmix for La1−xNdxPO4, which is positive and asymmetric and shows a maximum at x = 0.299 (ΔHmix=7.53±0.01kJmol−1) at 298 K.",
keywords = "Actinides, Crystal structure, Enthalpy of mixing, Monazite, Nuclear waste, Solid solution",
author = "H. Schlenz and J. Dellen and P. Kegler and C. Gatzen and C. Schreinemachers and A. Shelyug and M. Klinkenberg and A. Navrotsky and D. Bosbach",
note = "Funding Information: This work was supported by the German Research Association (Deutsche Forschungsgemeinschaft DFG; Project-No. SCHL495/3-1 ). The financial support is gratefully acknowledged. Special thanks go to H. Curtius and Z. Paparigas for the support of the IR measurements, to A. Bukaemskiy for supporting the pellet preparation, and to P. Kowalski and V. Vinograd for very fruitful discussions (all Forschungszentrum J{\"u}lich, IEK-6). The calorimetric studies were supported as part of the Materials Science of Actinides, an Energy Frontier Research Center funded by the U.S. Department of Energy , Office of Science , Office of Basic Energy Sciences [Grant DESC0001089 ]. Funding Information: This work was supported by the German Research Association (Deutsche Forschungsgemeinschaft DFG; Project-No. SCHL495/3-1). The financial support is gratefully acknowledged. Special thanks go to H. Curtius and Z. Paparigas for the support of the IR measurements, to A. Bukaemskiy for supporting the pellet preparation, and to P. Kowalski and V. Vinograd for very fruitful discussions (all Forschungszentrum J{\"u}lich, IEK-6). The calorimetric studies were supported as part of the Materials Science of Actinides, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences [Grant DESC0001089]. Publisher Copyright: {\textcopyright} 2018 Elsevier Inc.",
year = "2019",
month = feb,
doi = "10.1016/j.jssc.2018.11.040",
language = "English (US)",
volume = "270",
pages = "470--478",
journal = "Journal of Solid State Chemistry",
issn = "0022-4596",
publisher = "Academic Press Inc.",
}