X-Ray Studies of Quasi Crystals, Absolute Determination of Structure Factors

本探索性研究计划将利用内部多重布拉格散射的新技术来解决准晶体（QC）结构因子的相位确定问题。质量控制来自铝铜铁系统。多次散射技术的目标是将x射线反射强度的变化与多次散射中涉及的结构因素的相对相位联系起来。该技术已用于有机晶体，但尚未应用于质谱仪。项目的第二部分涉及选定结构因素的绝对测量。这是迈向完全确定原子位置的不可缺少的一步。该项目将包括确定弹性散射与非弹性康普顿散射的比率。如果成功，那么获得的信息将用于区分相互竞争的qc模型。//

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.//