The heat capacities of U3As4and Th3As4

✍ Scribed by A. Blaise; R. Lagnier; R. Troc; Z. Henkie; P. J. Markowski; M. J. Mortimer

• Book ID: 104626383
• Publisher: Springer US
• Year: 1980
• Tongue: English
• Weight: 501 KB
• Volume: 39
• Category: Article
• ISSN: 0022-2291
• DOI: 10.1007/bf00115623

✦ Synopsis

The heat capacities of the arsenides of uranium (U3As4) and thorium (Th3As4) have been measured in the temperature range 5-300 K. A sharp A-shaped anomaly at 195.8 K, associated with the ferromagnetic transition, was observed in U3As4. The smooth specific heat curve Cp(T) for nonmagnetic analog Th3As4 has been used to determine the lattice contribution to the heat capacity of U3As4. The resulting magnetic entropy at 290 K has been estimated as 10.67 J/K mole of U atom, which is close to the theoretical R In 4 value. This fact is interpreted in terms of crystal field interactions in the crystal lattice with $4 point symmetry. Critical entropy and energy parameters are compared with the theoretical predictions for 3d lsing and Heisenberg models. The critical coefficients are also considered.