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The p-T phase diagram of ammonium hexafluoroaluminate / M. V. Gorev [et al.]> // J. Phys.: Condens. Matter. - 2002. - Vol. 14, Is. 25. - P. 6447-6453, DOI 10.1088/0953-8984/14/25/312. - Cited References: 17
. - ISSN 0953-8984РУБ Physics, Condensed Matter Рубрики: NUCLEAR MAGNETIC-RESONANCE TRANSITIONS MOTIONS F-19 H-1 Кл.слова (ненормированные): Entropy -- Hydrostatic pressing -- Mathematical models -- Order disorder transitions -- Phase diagrams -- Specific heat of solids -- Ammonium hexafluoroaluminate -- Crolite -- Elpasolite -- Ammonium compounds Аннотация: The heat capacity and the effect of hydrostatic pressure on structural phase transitions in ammonium hexafluoroaluminate, (NH4)(3)AlF6, have been studied. Two heat capacity anomalies have been found with maxima at T-1 = 218.5 +/- 0.5 K and T-2 = 179 +/- 2 K. Respective entropy changes of phase transitions are DeltaS(1) = 15.3 +/- 0.5 J mol(-1) K-1 and DeltaS(2) = 2.5 +/- 0.5 J mol(-1) K-1. It is shown that the p-T phase diagram of this compound is rather complex and contains a triple point (p(tp) = 0.12 GPa, T-tp = 221 K) and high-pressure phase. The mechanism of transformations and generalized p-T phase diagram for compounds of the (NH4)(3)(MF6)-F-III family are discussed within the framework of the rotational order-disorder model.
WOS, Scopus, Читать в сети ИФ Держатели документа: LV Kirenskii Inst Phys, Krasnoyarsk 660036, Russia Inst Chim Mat Condensee Bordeaux, F-33608 Pessac, France ИФ СО РАН L. V. Kirensky Institute of Physics, 660036 Krasnoyarsk, Russian Federation Institut de Chimie de la Matiere Condensee de Bordeaux, 33608 Pessac, France Доп.точки доступа: Gorev, M. V.; Горев, Михаил Васильевич; Flerov, I. N.; Флёров, Игорь Николаевич; Tressaud, A.; Durand, E. } Найти похожие
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