Thermodynamic properties of the gaseous barium silicates BaSiO2 and BaSiO3

In the present study, the stability of gaseous barium silicates was confirmed by the high temperature mass spectrometry. On the basis of equilibrium constants measured for gas-phase reactions, the standard formation enthalpies were determined for gaseous barium silicates as (−510 ± 15) kJ · mol−1 and (−884 ± 18) kJ · mol−1 at 298 K; standard atomization enthalpies as (1637 ± 17) kJ · mol−1 and (2318 ± 20) kJ · mol−1 at 298 K for BaSiO2 and BaSiO3, respectively. Based on the results obtained the critical analysis of the literature data was carried out.