Interconnection of the parameters obtained from the dielectric spectrum of CaF₂ doped with ErF₃ and YbF₃

Abstract

A model has been suggested long ago that interconnects point defect parameters with bulk properties. On this basis, the ra‐tio of the migration entropy sm and the migration enthalpy hm should be equal to a bulk quantity. The validity of this prediction is studied here for the migration sm deduced from the pre‐exponential factor τ0 over the activation energy E involved in the Arrhenius relation τ = τ0 exp (E /kT) for the relaxation time τ. The study is focused on the so called RI‐relaxation in CaF2 doped with ErF3 and YbF3. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)