Features of Ca1-xYxF2+x solid solution heat capacity behavior: diffuse phase transition
https://doi.org/10.17586/2220-8054-2023-14-2-279-285
Abstract
A series of single crystals of a Ca1-xYxF2+x solid solution with a fluorite structure containing 1 19 mol.% YF3 (x =0.01–0.19) has been grown. Thermal analyzer STA 449 F3 Jupiter in DSC mode recorded the temperature dependences of the heat capacity Cp(T) in the temperature range from the room temperature to 1300 C. Adiffuse phase transition in the solid state for concentrations x =0.01–0.03 is fixed as an anomaly on the Cp(T) curves with a maximum at 1150 50 C. With an increase in the content of YF3 (x =0.05–0.19), a very wide structured peak is recorded in the range of 650–1100 C. The heat capacity anomaly is associated with the reversible rearrangement of defect nanoclusters, which affects the change in the anion sublattice.
Keywords
CaF2–YF3 phase diagram,
inorganic fluorides,
fluorite,
diffuse phase transition,
solid solution,
heterovalent isomorphism,
defect clusters
Supporting agencies: Authors express their sincere gratitude to E.V. Chernova for her most kind assistance in the preparation of the present manuscript. The study was funded by grant of Russian Science Foundation No. 22-13-00167, https://rscf.ru/project/22-13-00167.
About the Authors
A. A. Alexandrov
Prokhorov General Physics Institute of the Russian Academy of Sciences; Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences
Russian Federation
Russian Federation
Alexander A. Alexandrov
Vavilova str., 38, Moscow 119991
Leninskii pr. 31, Moscow, 119991
A. D. Rezaeva
Prokhorov General Physics Institute of the Russian Academy of Sciences
Russian Federation
Russian Federation
Anna D. Rezaeva
Vavilova str., 38, Moscow 119991
V. A. Konyushkin
Prokhorov General Physics Institute of the Russian Academy of Sciences
Russian Federation
Russian Federation
Vasilii A. Konyushkin
Vavilova str., 38, Moscow 119991
A. N. Nakladov
ProkhorovGeneralPhysics Institute of the Russian Academy of Sciences
Russian Federation
Russian Federation
Andrey N. Nakladov
Vavilova str., 38, Moscow 119991
S. V. Kuznetsov
Prokhorov General Physics Institute of the Russian Academy of Sciences
Russian Federation
Russian Federation
Sergey V. Kuznetsov
Vavilova str., 38, Moscow 119991
P. P. Fedorov
Prokhorov General Physics Institute of the Russian Academy of Sciences
Russian Federation
Russian Federation
Pavel P. Fedorov
Vavilova str., 38, Moscow 119991
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For citations:
Alexandrov A.A., Rezaeva A.D., Konyushkin V.A., Nakladov A.N., Kuznetsov S.V., Fedorov P.P. Features of Ca1-xYxF2+x solid solution heat capacity behavior: diffuse phase transition. Nanosystems: Physics, Chemistry, Mathematics. 2023;14(2):279-285. https://doi.org/10.17586/2220-8054-2023-14-2-279-285
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