  The energy of the electron wave packet interacting with lattice distortion,
is considered in anisotropic crystal. Anisotropy of the electron and phonon
spectra as well as of the electron-phonon interaction are taken into account.
The height of the barrier between free and self-trapped states is calculated in
dependence on the anisotropy parameters. The calculation is done numerically,
using continual aproximation. The analytical solution is obtained for some
cases of quasi-two and quasi-one-dimensional spectra. Key words: anisotropy;
polarons; barrier.
