Angle-resolved Cu and O photoemission intensities in CuO2 planes

Using a mapping from the three-band extended Hubbard model for cuprate supe rconductors into a generalized t-J model, and exact diagonalization of the latter in a 4 x 4 cluster, we determine the quasiparticle weight for destru ction of Cu or O electrons with definite wave vector k. We also derive an a pproximate but accurate analytical expression which relates the O intensity with the quasiparticle weight in the generalized t-J model. The k dependen ce of Cu and O intensities is markedly different. In particular the O inten sity vanishes for k = (0,0). Our results are relevant for the interpretatio n of angle-resolved photoemission experiments. [S0163-1829(99)03018-0].