Institute of Multidisciplinary Research for Advanced Materials, Tohoku University


LAST UPDATE 2021/05/04

  • 研究者氏名
    Researcher Name

    坂倉輝俊 Terutoshi SAKAKURA
    助教 Assistant Professor
  • 所属
    Professional Affiliation

    Institute of Multidisciplinary Research for Advanced Materials, Tohoku University

    計測研究部門 構造材料物性研究分野
    Division of Measurements, Structural Physics and Crystal Physics
  • 研究キーワード
    Research Keywords

    Single-crystal X-ray diffraction
    Electron density distribution
    Multiple diffraction
    Wave function
Research Subject
単結晶 X 線回折法における技術開発
Technical study of single-crystal X-ray diffraction

研究の背景 Background


Novel techniques to capture electron densities in materials quite clearly are required nowadays. In principle, the most promising probe of this kind is single-crystal X-ray diffraction (XRD). If any kinds of contaminations such as multiplediffractions (MDs) are eliminated, single-crystal XRD can capture spatial distribution of even only one valence electron in crystals.

研究の目標 Outcome


Through the development of wave-function-based refinement software and data collection technique reducing contaminations due to multiple diffractions, conventional XRD technique can become a sophisticated tool to investigate electron density distribution in crystals. Our objective is to overcome such technical difficulties and complexities in this field.

研究図Research Figure

Fig.1. Comparison of structure factor squared measured in MD-avoided and no MD-avoided methods for YMn2O5. For weak or forbidden reflections, most of the no MD-avoided reflections are larger than MD-avoided ones in a few orders due to MD. Fig.2. Experimentally observed orbital order of Ti-3d1 electrons in YTiO3. For no MD-avoided measurement (b), lobes of 3d electrons, which is clearly observed in MD-avoided measurement (a), cannot be observed. Isosurface level is ±1.3eÅ-3. Sky-blue is negative and yellow is positive, Fig.3. Electron density of ψ(t2g2,1A1) orbital illustrated by inverse Fourier transformation of structure factor calculated by our developing wavefunction based refinement software for a virtual crystal isostructural to YTiO3.

文献 / Publications

Acta Cryst. B,67,193(2011). ISOTOPES 誌, 60(3),131 (2011). Acta Cryst. E,66,i68(2010). Acta Cryst E,66,i80(2010).