Magnetic impurities in ( AB2) n polymeric chains

Abstract

The techniques of renormalization of interactions and transfer matrices are used to investigate spin polarization effects in ( AB 2) n chains, within a Hartree-Fock solution to a Hubbard diagonal hamiltonian approximation. The electronic structure of infinite chains is obtained and the magnetization of the system is examined for different values of the one-center interaction integrals U. It is observed that one third of the total available electronic states is associated to non-dispersive states localized on the B sites and that both the position in energy of these localized states and the gap width are controlled by the strength of the parameter U. The damped spin density wave resulting from the introduction of a substitutional impurity on an A center can then be calculated for different regions of the parameter space of the problem.