Abstract
Recent scanning tunneling microscopy studies have shown that local nanoscale pairing inhomogeneities are correlated with interstitial oxygen dopants in Bi2Sr2CaCu2O8+δ. Combining electrostatic and cluster calculations, in this paper the impact of a dopant on the local Madelung and charge transfer energies, magnetic exchange J, Zhang-Rice mobility and interactions with the lattice is investigated. It is found that electrostatic modifications locally increase the charge transfer energy and slightly suppress J. It is further shown that coupling to c-axis phonons is strongly modified near the dopant. The combined effects of electrostatic modifications and coupling to the lattice yield broadened spectral features, reduced charge gap energies and a sizeable local increase of J. This implies a strong local interplay between antiferromagnetism, polarons and superconducting pairing.