J. E. Hirsch and F. Marsiglio, Phys. Rev. B 41, 2049 (1990)
We study the properties of a model Hamiltonian to describe conduction by holes in a lattice of 02- anions. An attractive interaction between nearest-neighbor holes with antiparallel spins exists in certain parameter regimes. The physical mechanism giving rise to this attraction is discussed. The model predicts extended s-wave superconductivity with high critical temperatures with dependence on hole density consistent with observations on oxides.