Thermal properties of perovskite RCeO3 (R = Ba, Sr)

•(Ba,Sr)CeO3 are high temperature protonic conductor materials.•This makes their thermal properties very interesting.•MRIM has successfully predicted the thermodynamic properties.•The computed results are in good agreement with the available experimental data.•Present results will serve as guide to experimental workers in future.

We have investigated the bulk modulus and thermal properties of proton conducting perovskite RCeO3 (R = Ba, Sr) for the first time by incorporating the effect of lattice distortion in modified rigid ion models (MRIM). The computed bulk modulus, specific heat, thermal expansion coefficient and other thermal properties of BaCeO3 and SrCeO3 reproduce well with the available experimental data. In addition the cohesive energy (ϕ), molecular force constant (f), reststrahlen frequency (ν), Debye temperature (θD) and Gruneisen parameter (γ) are also reported and discussed. The specific heat results can further be improved by taking into account the spin and the orbital ordering contribution in the specific heat formulae.