Abstract
The equation of state of perovskite-structure CsCaF3 has been calculated using Gordon-Kim pair potentials in the quasi-harmonic approximation. Agreement with experimental results is reasonably good for phonon frequencies and equation-of-state properties. Recently, similar calculations for RbCaF3 were found to be consistent with an observed displacive phase transition in this material. Significantly, the same theory predicts the absence of any displacive transition in CsCaF3, in agreement with experiment.