Phase transitions of K2TaF7 within 680–800°C

• Autorzy: Ladislav Kosa , Iveta Macková , Ivo Proks , Ondrej Pritula , Ľubomír Smrčok , Miroslav Boča , Håkan Rundlőf
• Języki publikacji: EN

Abstrakty

EN

Three thermal effects on heating/cooling of K2TaF7 in the temperature interval of 680–800°C were investigated by the DSC method. The values determined for the enthalpy change of the individual processes are: ΔtransIIHm(K2TaF7; 703°C) = 1.7(2) kJ mol−1, ΔtransIHm(K2TaF7; 746°C) = 19(1) kJ mol−1 and ΔtransIIIHm(K2TaF7; 771°C) = 13(1) kJ mol−1. The first thermal effect was attributed to a solid-solid phase transition; the second to the incongruent melting of K2TaF7 and the third to mixing of two liquids. These findings are supported by in situ neutron powder diffraction experiments performed in the temperature interval of 654–794°C. [...]

Słowa kluczowe

EN

K2TaF7; Phase transition; Enthalpy changes; DSC; Neutron powder diffraction

• Czasopismo: Open Chemistry
• Rocznik: 2008
• Tom: 6
• Numer: 1
• Strony: 27-32

Daty

wydano

2008-03-01

online

2008-03-01

Twórcy

autor

Ladislav Kosa

• Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-845 36, Bratislava, Slovak Republic

autor

Iveta Macková

• Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-845 36, Bratislava, Slovak Republic

autor

Ivo Proks

• Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-845 36, Bratislava, Slovak Republic

autor

Ondrej Pritula

• Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-845 36, Bratislava, Slovak Republic

autor

Ľubomír Smrčok

• Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-845 36, Bratislava, Slovak Republic

autor

Miroslav Boča

• Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-845 36, Bratislava, Slovak Republic,

autor

Håkan Rundlőf

• Institutionen főr Materialkemi, Uppsala Universitet, Box 538, 751 21, Uppsala, Sweden

Bibliografia

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• [7] A.I. Agulyansky and V.A. Bessonova, Zh. Prikl. Khim. 56, 489 (1983)(in Russian)
• [8] K. Adamkovičová, P. Fellner, L. Kosa, P. Lazor, I. Nerád, I. Proks, Thermochim. Acta, 191, 57 (1991) http://dx.doi.org/10.1016/0040-6031(91)87237-Q[Crossref]
• [9] K. Adamkovičová, L. Kosa, I. Nerád, I. Proks, Thermochim. Acta, 287, 1 (1996) http://dx.doi.org/10.1016/0040-6031(96)02993-0[Crossref]
• [10] V. Langer, Ľ. Smrčok, M. Boča, Acta Cryst. E62, i91 (2006)

Identyfikatory

DOI

10.2478/s11532-007-0056-2