  A dressing technique is used to improve zero range potential (ZRP) model. We
consider a Darboux transformation starting with a ZRP, the result of the
"dressing" gives a potential with non-zero range that depends on a seed
solution parameters. Concepts of the partial waves and partial phases for
non-spherical potential are used in order to perform Darboux transformation.
The problem of scattering on the regular X$_{\hbox{n}}$ and YX$_{\hbox{n}}$
structures is studied. The results of the low-energy electron-molecule
scattering on the dressed ZRPs are illustrated by model calculation for the
configuration and parameters of the silane ($\hbox{SiH}_4$) molecule.
\center{Key words: low-energy scattering, multiple scattering,
Ramsauer-Townsend minimum, silane, zero range potential.
