The thermodynamic functions of 4f metal dichlorides in the condensed state

The temperature dependences of heat capacity were obtained for solid 4f metal dichlorides LnCl(2) (Ln = La,...,Lu) in the quasi-harmonic approximation over the temperature range from 0 K to the melting point T-m. The correction for systematic underestimation of the lattice heat capacity component in this approximation was determined from high-temperature EuCl2 heat capacity measurements. The literature data were analyzed to select the temperatures and enthalpies of phase transitions and estimate the heat capacities of the substances in the liquid state. The thermodynamic functions of LnCl(2) in the condensed state were calculated over the temperature range 298.15-2000 K. The calculations were performed taking into account excited electronic states whose energies did not exceed 10000 cm(-1).