从x射线粉末数据获得非等效本征重叠衍射的合理衍射强度

提出一种非等效本征重叠衍射强度合理分配的方法——位置待定的原子强度贡献迭代分配法(IDM-UAIC),并用已知结构的模拟粉末衍射数据进行了验证.IDM-UAIC利用可靠的晶体学和结构化学知识，交替进行结构解析和强度分离.结果表明：如果可以通过等效本征重叠足够精确地确定总体散射能力的30%，结构就可能解出.对于55个（不含三角晶系用菱形单胞表示的5种空间群）强度均分不合理的空间群，IDM-UAIC具有明显的优越性；而对于强度可均分的空间群，IDM-UAIC与简单均分法等效.关键词：非等效本征重叠衍射强度原子强度贡献迭代分配法

A new approach to extract reliable intensities of non-equivalent systematical overlapping reflections from powder diffraction data

A new approach to extract reliable intensities from systematical non-equivalent overlapping reflections has been proposed and tested by simulated powder diffraction pattern of known structures. By using both crystallographic and structural chemistry knowledge, the IDM-UAIC reconstructs the intensities and solves the structure through an iterative procedure. The results show that IDM-UAIC succeeds when more than 30% of the total scattering power can be located in a reasonable precise from the equivalent systematical overlapping reflections. The IDM-UAIC procedure is superior to the simple equi-partition methods for the nonequivalent systematical overlapping reflections while it is equivalent to simple equi-partition methods for the equivalent systematical overlapping reflections.