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Journal
2007 | 5 | 2 | 508-515
Article title

Thermochemical properties of the Fe-analogue of cryolite, Na3FeF6

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Abstracts
EN
Relative enthalpies for low-and high-temperature modifications of Na3FeF6 and for the Na3FeF6 melt have been measured by drop calorimetry in the temperature range 723–1318 K. Enthalpy of modification transition at 920 K, δtransH(Na3FeF6, 920 K) = (19 ± 3) kJ mol−1 and enthalpy of fusion at the temperature of fusion 1255 K, δfusH(Na3FeF6, 1255 K) = (89 ± 3) kJ mol−1 have been determined from the experimental data. Following heat capacities were obtained for the crystalline phases and for the melt, respectively: C p(Na3FeF6, cr, α) = (294 ± 14) J (mol K)−1, for 723 = T/K ≤ 920, C p(Na3FeF6, cr, β) = (300 ± 11) J (mol K)−1 for 920 ≤ T/K = 1233 and C p(Na3FeF6, melt) = (275 ± 22) J (mol K)−1 for 1258 ≤ T/K ≤ 1318. The obtained enthalpies indicate that melting of Na3FeF6 proceeds through a continuous series of temperature dependent equilibrium states, likely associated with the production of a solid solution. [...]
Keywords
Publisher

Journal
Year
Volume
5
Issue
2
Pages
508-515
Physical description
Dates
published
1 - 6 - 2007
online
27 - 2 - 2007
Contributors
author
  • Institute of Inorganic Chemistry, Slovak Academy of Sciences, 845 36, Bratislava, Slovak Republic, ivan.nerad@savba.sk
  • Institute of Inorganic Chemistry, Slovak Academy of Sciences, 845 36, Bratislava, Slovak Republic
References
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Document Type
Publication order reference
Identifiers
YADDA identifier
bwmeta1.element.-psjd-doi-10_2478_s11532-007-0015-y
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