ELECTRONIC-STRUCTURE OF BI2SR2CUO6 (BI2201) - DESCRIPTION OF THE COPPER-OXYGEN BANDS CLOSE TO THE FERMI ENERGY

Photoemission results in the cuprate superconductors [1] show that clo se to the Fermi energy and around ($) over bar M point flat copper-oxy gen bands with small bismuth contribution appear in an extended region . In this paper we determine from first principles the bandstructure o f Bi2201 using the FP-LMTO method within the LDA. We show that the pos ition relative to the Fermi energy and the dispersion of the calculate d copper-oxygen bands are dependent on surface effects. Surface recons truction is also analyzed.