Abstract
After a short outline of the vibronic features of the local Jahn-Teller effect (E g ⊗ ε g coupling) the cooperative aspects — in particular the various order patterns of the elongated octahedra in Cu(II) solids — are reviewed. While the elastic interactions can be described by energy terms of Qε symmetry, the local Jahn-Teller effect has Qθ symmetry (ϕ = 0). Phase transitions in dependence on the Cu(II) concentration are analysed in detail for oxidic ordered perovskites Ba(Sr)2Zn(Ni)1-x CuxW(Te)O6, which exhibit ferrodistortive order patterns connected with first order phase transitions at high x-values. At lower x-values at the short-range order scale elastic Qε-type strains prevail as in the cases of antiferrodistortive order, leading to continuous phase transitions. Here, the cluster distribution has been successfully analysed by EPR spectroscopy.
Similar content being viewed by others
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Reinen, D., Wellern, H. & Wegwerth, J. Jahn-Teller-type phase transitions in oxide ceramics and other solids with Cu(II) — from the viewpoint of a solid state chemist. Zeitschrift für Physik B Condensed Matter 104, 595–600 (1997). https://doi.org/10.1007/s002570050494
Published:
Issue Date:
DOI: https://doi.org/10.1007/s002570050494