Geometrical and dynamical aspects of the correlated electron pair emissionfrom ordered materials

The scattering of N-body correlated systems from a non-overlapping multi-ce nter periodic potential is formulated in terms of scattering path operators . An expansion of the total T-matrix in terms of scattering path operators is derived. Special attention is devoted to the separation of the geometric al arrangement of the scatterers from the internal correlation of the scatt ered compound. The role of internal correlation is illustrated in the case of the scattering of correlated electron pairs from a perfect crystal poten tial and the electron-pair excitation from core levels into the vacuum upon a photon absorption.