Graphical technique for the generalized Hubbard model

Perturbation theory is constructed for evaluating Green's functions in the system of hybrydized $s$- and $d$-electrons with strong inter-atomic correlation. Summation of the perturbation theory series is performed by means of the diagram technique for Hubbard operators. It is shown that the scattering of the $s$-electrons on the sites gives rise to the logarithmic renormalization of the $d$-levels, the nature of which is the same as in the one-impurity Anderson model.