X-ray Analysis of Electron Density -Theory and Experiment-

当前国际合作研究的目标是交换俄罗斯和日本之间的研究中的X射线电子密度研究，并在21世纪开发X射线晶体学。日本对我们的精炼方法和俄罗斯研究人员基于原子或分子轨道（X射线AO/MO分析）和电子密度（多重精炼），尊重。X射线AO分析已经成功地应用于过渡金属复合体。如何进行X射线MO分析并没有成功，Perovskite KNiF D23 D2晶体的电子密度已经研究了因为晶体场的最高对称性，在任何两种方法都可以轻松地比较。它是用两种方法分析的，并给出了几乎相同的电子配置。Topological analysis of the electron density of KNiF-D23-D2 revealed that the topological picture of the atomic interactions differed from that resulting from the classic crystal chemistry molecular orbital （CMO）， in which the periodicity of crystals is taken into account， should be used。Highly accurate measurement is necessary for X-ray MO analysis。VCIP方法被用来衡量强度，从噪音到空气散射X射线。对KNiF-D23-D2的VCIP测量与四个圆圈差计进行了比较。两者都得到了几乎相同的变形密度和R因子分别为0.4%和0.8%（四圈和VCIP测量）。自21世纪21世纪IP上差异X射线的缓慢事件和问题作为一种设备的高准确强度测量。

The aim of the present international cooperative research is to exchange theoretical methods and experimental techniques in X-ray electron density study between researches in Russia and Japan and to Develop X-ray crystallography in the 21-st century. The methods of refinements of us in Japan and researchers in Russia are based on atomic or molecular orbitals (X-ray AO/MO analysis) and electron density (multiple refinement), respectively. The X-ray AO analysis has been successfully applied to transition metal complexes. However the X-ray MO analysis has not been successful.The electron density of perovskite KNiFィイD23ィエD2 crystals was studied because of the highest symmetry of the crystal field, in which both methods could be easily compared. It was analyzed with the both method and give almost the same electron configuration. Topological analysis of the electron density of KNiFィイD23ィエD2 revealed that the topological picture of the atomic interactions differed from that resulting from the classic crystal chemistry molecular orbital (CMO), in which the periodicity of crystals is taken into account, should be used.Highly accurate measurement is necessary for X-ray MO analysis. The VCIP method was devised to measure intensities free from the noise due to air-scattered X-rays. The VCIP measurement of KNiFィイD23ィエD2 was compared with that by a four-circle diffractometer. Both gave almost the same deformation density and R-factors were 0.4% and 0.8% for four-circle and VCIP measurements, respectively. Since slant incidence of diffracted X-rays onto IP and problems as a device for highly accurate intensity measurement in 21-st century.