The thermodynamic properties of Ce2O3(s) fromT→ 0 K to 1500 K

Revisiting the thermophysical properties of the A-type hexagonal lanthanide sesquioxides between temperatures of 5 K and 1000 K

“…The heat capacity and enthalpy results of Huntelaar et al (5) would support the presence of a mixed oxide phase of cerium as they discuss, (5) but probably not as noticeable as suggested by the Pankratz data. (12) No further attempt to justify the thermodynamic functions above T = 420 K based on 0 K is made in table 3, a brief summary of the Huntelaar low temperature data providing expedient clarity for the discussion below.…”

“…The transition observed for Ce 2 O 3 at T = 1000 K (12) must have been the formation of a mixed phase with CeO 2 upon which Justice and Westrum (10) measured their heat capacities. One would expect that the data of Weller and King (9) would best fit that of Huntelaar et al (5) which it does with the ensuing cautionary comments.…”

“…(8) Adjuvant low-temperature measurements for Ce 2 O 3 are given from T = 50 K to 300 K by Weller and King (9) and from T = 5 K to 350 K by Justice and Westrum. (10) High-temperature enthalpy increments have been reported for La 2 O 3 (298 T /K 1800) (8) and (303 T /K 1172); (11) for Ce 2 O 3 (298 T /K 1000); (5,12) for Pr 2 O 3 (298 T /K 1600), (13) and for Nd 2 O 3 (303 T /K 1172) (11) and (298 T /K 1795). (14) Up to now no attempt has been made to join the low-temperature heat-capacity data with the super-ambient enthalpy increment data, yielding a consistently assessed curve (functional basis T = 0 K) covering the entire temperature range reported for the A-type sesquioxides.…”

“…(2) Nonetheless, a persuasive interest exists in resolving the heat capacities and the optical properties of the first four members of this series, La 2 is instrumental in correlating data for the corresponding binary insulators such as the sesquisulfides (2) and conductors such as the hexaborides. (3) Heat-capacity measurements for La 2 O 3 and Nd 2 O 3 (5 T /K 350) by Justice and Westrum, (4) Ce 2 O 3 (3 T /K 420) by Huntelaar et al (5) and Pr 2 O 3 (5 T /K 320) by Lutsareva, Naumov, and Paukov (6) have been made. Other measurements for La 2 O 3 and Nd 2 O 3 have been reported by Goldstein et al (12 T /K 300) (7) and for La 2 O 3 by King et al (50 T /K 300).…”

Cerium Valence Change in the Solid Solutions Ce(Rh1-xRux)Sn

“…They reported also a small λ -shaped anomaly at 5.5 K in CeNi 2 Sn arising from a minor Ce 2 O 3 impurity. The thermodynamic investigations on Ce 2 O 3 have been performed by Huntelaar et al [34]. A minor Ce 2 O 3 phase could also describe the small amount of stable Ce 3+ determined by fitting the susceptibility data with the ICF model.…”