Thermodynamics of the Lanthanide Trifluorides. I. The Heat Capacity of Lanthanum Trifluoride, LaF₃ from 5 to 350°K and Enthalpies from 298 to 1477°K

Author

William G. Lyon
Darrell W. Osborne
Howard E. Flotow
Fernande Grandjean, Missouri University of Science and TechnologyFollow
Ward N. Hubbard
Gerald K. Johnson

Abstract

The heat capacity of a sample of LaF₃ was determined in the temperature range 5-350°K by aneroid adiabatic calorimetry and the enthalpy from 298.15 to 1477°K by drop calorimetry. The heat capacity at constant pressure C°_p(298.15°K), the entropy S°(298.15°K), the enthalpy [H°(298.15°K)-H°(0)] and the Planck function -[G°(298.15°K)-H°(0)]/298.15°K; were found to be (90.29±0.09) J °K^-1·mole^-1, (106.98±0.11) J °K^-1·mole^-1, (16717±17) J mole^-1, and (50.91±0.05) J °K ^-1·mole^-1. The thermal functions from the present research were extended up to the melting temperature (1766°K) by combination with previously published results. The anomalously high heat capacity from about 1100 to 1766°K is discussed.

Recommended Citation

W. G. Lyon et al., "Thermodynamics of the Lanthanide Trifluorides. I. The Heat Capacity of Lanthanum Trifluoride, LaF₃ from 5 to 350°K and Enthalpies from 298 to 1477°K," Journal of Chemical Physics, vol. 69, no. 1, pp. 167 - 173, American Institute of Physics (AIP), Jul 1978.

The definitive version is available at https://doi.org/10.1063/1.436381

Department(s)

Chemistry

International Standard Serial Number (ISSN)

0021-9606

Document Type

Article - Journal

Document Version

Final Version

File Type

text

Language(s)

English

Rights

© 1978 American Institute of Physics (AIP), All rights reserved.

Publication Date

01 Jul 1978