It is shown that the spin-fermion model found to be an effective low-energy implementation of the three-band Emery model after Wannier transformation of px- and py-orbitals in the oxygen ions subsystem is reduced to the generalized Kondo lattice model. Its essential feature is the presence of spin-correlated hoppings of the current carriers between distant cells. Numerical calculations of the spin-polaron spectrum demonstrate the important role of the distant hoppings.
@article{arxiv.1606.04727,
title = {The generalized Kondo lattice model and its spin-polaron implementation for cuprates by projection method},
author = {V. V. Val'kov and D. M. Dzebisashvili and A. F. Barabanov},
journal= {arXiv preprint arXiv:1606.04727},
year = {2016}
}