Computer modelling and brillouin scattering studies of high temperature disorder in CdF2

Abstract

Abstract The reliability of the lattice simulations depends on the quality of the potentials used. Hence, the interionic potentials of CdF2 were derived and used in the calculations of the crystal bulk data. The temperature dependences of elastic constants is investigated. Elastic properties are predicted. The complementary studies using Brillouin scattering methods, show that the disorder at the transition temperature (Tc ≊ 900 K) results in an abrupt decrease in the elastic constant C11. Both methods show that the elastic constants linearly decrease with increasing temperature within the low temperature region. Similar trends have been observed in other fluorites. This shows that our interionic potentials reproduce the behaviour of CdF2 reasonably well.