This exploratory research proposal will use the novel technique of internal multiple Bragg scattering to address the problem of phase determination of structure factors of a quasi-crystal (QC). The QC is from the Al-Cu-Fe system. The object of the multiple scattering technique is to relate changes in intensity of x-ray reflections to relative phases of the structure factors involved in the multiple scattering. The technique has been used for organic crystals but has not been applied to QCs. The second part of the project deals with absolute measurements of selected structure factors. This is an indispensable step towards a complete determination of atomic locations. The project will involve determination of the ratio of elastic scattering to inelastic Compton scattering. If successful, the information so obtained would then be used to distinguish between competing models of QCs.//
