University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 10 2 1999 06 01 A NUMERICAL RENORMALIZATION GROUP APPROACH FOR AN ELECTRON-PHONON INTERACTION - 31494 EN Journal Article A finite chain calculation in terms of Hubbard X-operators is explored by setting up a vibronic Harniltonian. The model conveniently transformed into a form so that in the case of strong coupling a numerical renormalization group approach is applicable. To test the technique, a one particle Green function is calculated for the model Harniltonian https://jsciences.ut.ac.ir/article_31494_db07748a120b8752dcac49ddfe281b71.pdf