najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМО10.17586/2220-8054-2023-14-2-279-285najo-155Research ArticleCHEMISTRY AND MATERIALS SCIENCEХИМИЯ И НАУКА О МАТЕРИАЛАХFeatures of Ca1-xYxF2+x solid solution heat capacity behavior: diffuse phase transitionОсобенности поведения теплоемкости твердого раствора Ca1-xYxF2+x: размытый фазовый переходhttps://orcid.org/0000-0001-7874-7284АлександровА. А.AlexandrovA. A.

Alexander A. Alexandrov

Vavilova str., 38, Moscow 119991

Leninskii pr. 31, Moscow, 119991

alexandrov1996@yandex.ruРезаеваА. Д.RezaevaA. D.

Anna D. Rezaeva

Vavilova str., 38, Moscow 119991

1032192969@rudn.ruhttps://orcid.org/0000-0002-6028-8937КонюшкинВ. А.KonyushkinV. A.

Vasilii A. Konyushkin

Vavilova str., 38, Moscow 119991

vasil@lst.gpi.ruhttps://orcid.org/0000-0002-4060-8091НакладовА. Н.NakladovA. N.

Andrey N. Nakladov

Vavilova str., 38, Moscow 119991

andy-nak@yandex.ruhttps://orcid.org/0000-0002-7669-1106КузнецовС. В.KuznetsovS. V.

Sergey V. Kuznetsov

Vavilova str., 38, Moscow 119991

kouznetzovsv@gmail.comhttps://orcid.org/0000-0002-2918-3926ФедоровП. П.FedorovP. P.

Pavel P. Fedorov

Vavilova str., 38, Moscow 119991

ppfedorov@yandex.ruИнститут общей физики им. А.М. Прохорова Российской академии наукProkhorov General Physics Institute of the Russian Academy of Sciences; Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of SciencesИнститут общей физики им. А.М. Прохорова Российской академии наукProkhorov General Physics Institute of the Russian Academy of SciencesИнститут общей физики им. А.М. Прохорова Российской академии наукProkhorovGeneralPhysics Institute of the Russian Academy of Sciences202303062025142279285Copyright © Alexandrov A.A., Rezaeva A.D., Konyushkin V.A., Nakladov A.N., Kuznetsov S.V., Fedorov P.P., 20252025Александров А.А., Резаева А.Д., Конюшкин В.А., Накладов А.Н., Кузнецов С.В., Федоров П.П.Alexandrov A.A., Rezaeva A.D., Konyushkin V.A., Nakladov A.N., Kuznetsov S.V., Fedorov P.P.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://nanojournal.ifmo.ru/jour/article/view/155

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.

Выращена серия монокристаллов твердого раствора Ca1-xYxF2+x флюоритовой структуры с содержанием 1 - 19 мол.% YF3  (х = 0.01 – 0.19). На термоанализаторе STA 449 F3 Jupiter сняты температурные зависимости теплоемкости Cp(T) в интервале температур от комнатной до 1300 °С. Размытый фазовый переход в твердом состоянии для концентраций х = 0.01 – 0.03 фиксируется в виде аномалии на кривых Cp(T) с максимумом при 1150 ± 50 °С. При увеличении содержания YF3 (х = 0.05 – 0.19) фиксируется очень широкий структурированный пик в интервале 650 -1100 °С. Аномалия теплоемкости связана с обратимой перестройкой дефектных нанокластеров, которая влияет на изменение анионной подрешетки.

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