Heat capacity of Pb$_{10-x}$Nd$_{x}$(GeO$_{4}$)$_{2+x}$(VO)$_{4-x}$ ($x$ = 0–3) apatites

The Pb$_{10-x}$Nd$_{x}$(GeO$_{4}$)$_{2+x}$(VO)$_{4-x}$ ($x$ = 0–3) compounds with the apatite structure have been synthesized from PbO, Nd$_{2}$O$_{3}$, GeO$_{2}$, and V$_{2}$O$_{5}$ oxides by the solid-state synthesis with successive burning in air within 773–1073 K. The high-temperature heat capacity of the compounds obtained was determined by differential scanning calorimetry. The $C_{p}=f(T)$ data have been used to evaluate their thermodynamic properties (enthalpy increment, entropy change, and reduced Gibbs energy).