Thermodynamics of tetraphenylantimony benzoate Ph4SbOC(O)Ph

Highlights: • We report for the first time the temperature dependence of heat capacity of tetraphenylantimony benzoate. • The fusion of the compound has been specified and its standard thermodynamic characteristics were analyzed. • The thermodynamic functions of Ph₄SbOC(O)Ph in crystalline and liquid states were calculated. • The energy of Ph₄SbOC(O)Ph combustion was measured. • The standard characteristics of the substance formation in the crystalline state at T = 298.15 K were calculated. -- Abstract: In the present research, the temperature dependence of the heat capacity $C_{p,m}^o$ = f(T) of tetraphenylantimony benzoate Ph₄SbOC(O)Ph has been measured in the range T = (5 and 480) K in the precision adiabatic vacuum and differential scanning calorimeters and reported for the first time. In the studied temperature region the melting of the compound has been revealed and its standard thermodynamic characteristics were analyzed. The standard thermodynamic functions (p° = 0.1 MPa) of Ph₄SbOC(O)Ph in crystalline and liquid states were calculated with the obtained experimental data: $C_{p,m}^o/R$, ${\Delta }_0^T{H}_{\text{m}}^{\text{o}}/RT$, ${\Delta }_0^T{S}_m^o$/R and ${\Phi }_{\text{m}}^{\text{o}}$ = ${\Delta }_0^T{S}_m^o$ – ${\Delta }_0^T{H}_m^o$/T (where R is the universal gas constant) from T → 0 to 480 K. The energy of combustion of Ph₄SbOC(O)Ph was measured. The standard enthalpy of combustion, formation enthalpy, formation entropy, Gibbs energy of formation of the substance in the crystalline state at T = 298.15 K were calculated. Comparison of thermodynamic properties was made for the derivatives of antimony studied in the present work, Ph₅Sb and other of type Ph₃SbX₂.