Title: PSEUDOSPIN-ELECTRON MODEL IN THE SELF-CONSISTENT GAUSSIAN FLUCTUATION APPROXIMATION
Author(s): I.V.Stasyuk, K.V.Tabunshchyk (Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii Str., 79011 Lviv, Ukraine)

Pseudospin-electron model with an effective many-body interaction between pseudospins via conducting electrons is investigated within the generalized random phase approximation scheme with the self-consistent inclusion of mean field type contributions (coming from the effective pseudospin interaction) as well as gaussian fluctuations of the mean field (which makes it possible to obtain more accurate results in the vicinity of the critical points). Using the approach proposed here, the expressions are obtained for the pseudospin correlation function, for pseudospin mean value, as well as for the grand canonical potential.

Key words: pseudospin-electron model, local anharmonicity, gaussian fluctuations
PACS: 71.10.Fd, 71.38.+i, 77.80.Bh, 63.20.Ry