Title: LOCAL ANHARMONIC EFFECTS IN HIGH-T_c SUPERCONDUCTORS. PSEUDOSPIN-ELECTRON MODEL
Authors: I.V.Stasyuk (Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii Str., 79011 Lviv, Ukraine)

Some aspects of physical phenomena in high-T$_{\rm c}$ crystals caused by anharmonicity of the crystal lattice are discussed. Appropriate theoretical models are considered. A review is given of the results obtained while investigating the pseudospin-electron model (PEM) when applied to the description of structural and dielectric instabilities, phase separations and bistability phenomena. The theoretical problems are analyzed arising in PEM when the strong short-range correlations and electron transfer are taken into account simultaneously.

Comments: Figs. 0, Refs. 48, Tabs. 0.