Photoelectron outgoing wave emitted from core state of excited atom will be scattered by near neighbor atoms.Scattered waves (object waves) which contain structural information of the environment around the excited atom interfere with the original one(reference wave)which propagates directly to the detector,and then a diffraction pattern,i.e.a photoelectron hologram,will be created.A complete 3 D image of the structure surrounding the emitter with at omic resolution can be reconstructed.This paper gives computer simulation for ca lculat ing photoelectron holograms of small atomic clusters on c(2×2) S/Ni(100) surface,in metal copper,and on puckered Cu2O plane of superconductor YBCO.

EXAFS analyses of YBCO doped with Pr approve that the O position in this system changes with the Pr concentration x. With increasing x, the deformation of CuO₂ plane greater, the O in the Cu-O chain nearer CuO₂ plane, the distance between Ba and O3 longer. All these tructure changes in the Y_1-xPr_xBa₂Cu₃O_7-δ system make the carrier density decreas and make the carrier strongly localize, which causes the change of superconductivity.