Three-beam convergent-beam electron diffraction for measuring crystallographic phases

被引:0
|
作者
Guo, Yueming [1 ]
Nakashima, Philip N. H. [1 ]
Etheridge, Joanne [1 ,2 ]
机构
[1] Monash Univ, Dept Mat Sci & Engn, Clayton, Vic 3800, Australia
[2] Monash Univ, Monash Ctr Electron Microscopy, Clayton, Vic 3800, Australia
来源
IUCRJ | 2018年 / 5卷
基金
澳大利亚研究理事会;
关键词
crystallographic phase problem; three-phase invariants; convergent-beam electron diffraction; structure determination; enantiomorph ambiguity; nanocrystals; dynamical studies; multiple scattering; INITIO STRUCTURE SOLUTION; X-RAY; SCATTERING INTENSITIES; SIMULTANEOUS REFLEXION; PRECESSION TECHNIQUE; STRUCTURAL PHASE; INVERSION; CRYSTALS; PATTERNS; TOMOGRAPHY;
D O I
10.1107/S2052252518012216
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Under almost all circumstances, electron diffraction patterns contain information about the phases of structure factors, a consequence of the short wavelength of an electron and its strong Coulombic interaction with matter. However, extracting this information remains a challenge and no generic method exists. In this work, a set of simple analytical expressions is derived for the intensity distribution in convergent-beam electron diffraction (CBED) patterns recorded under three-beam conditions. It is shown that these expressions can be used to identify features in three-beam CBED patterns from which three-phase invariants can be extracted directly, without any iterative refinement processes. The octant, in which the three-phase invariant lies, can be determined simply by inspection of the indexed CBED patterns (i.e. the uncertainty of the phase measurement is +/- 22.5 degrees). This approach is demonstrated with the experimental measurement of three-phase invariants in two simple test cases: centrosym-metric Si and non-centrosymmetric GaAs. This method may complement existing structure determination methods by providing direct measurements of three-phase invariants to replace 'guessed' invariants in ab initio phasing methods and hence provide more stringent constraints to the structure solution.
引用
收藏
页码:753 / 764
页数:12
相关论文
共 50 条
  • [21] Convergent-beam electron diffraction and electron microscope studies of decagonal quasicrystals
    Tanaka, M
    Tsuda, K
    Saitoh, K
    SCIENCE REPORTS OF THE RESEARCH INSTITUTES TOHOKU UNIVERSITY SERIES A-PHYSICS CHEMISTRY AND METALLURGY, 1996, 42 (01): : 199 - 205
  • [22] Performance of a new Ω-filter electron microscope on convergent-beam electron diffraction
    Tsuda, K
    Saitoh, K
    Terauchi, M
    Tanaka, M
    Kaneyama, T
    Tsuno, K
    Honda, T
    ELECTRON MICROSCOPY 1998, VOL 1: GENERAL INTEREST AND INSTRUMENTATION, 1998, : 251 - 252
  • [23] PARITY TABLES IN CONVERGENT-BEAM DIFFRACTION
    JACKSON, AG
    ULTRAMICROSCOPY, 1989, 30 (03) : 349 - 354
  • [24] INTERFACE STRUCTURES INVESTIGATED BY CONVERGENT-BEAM ELECTRON-DIFFRACTION
    SCHAPINK, F
    ULTRAMICROSCOPY, 1986, 19 (04) : 397 - 397
  • [25] LARGE-ANGLE CONVERGENT-BEAM ELECTRON-DIFFRACTION
    TANAKA, M
    SAITO, R
    UENO, K
    HARADA, Y
    JOURNAL OF ELECTRON MICROSCOPY, 1980, 29 (04): : 408 - 412
  • [26] SYMMETRY DETERMINATION BY CONVERGENT-BEAM DIFFRACTION
    EADES, JA
    EUREM 88, VOLS 1-3: TUTORIALS, INSTRUMENTATION AND TECHNIQUES / PHYSICS AND MATERIALS / BIOLOGY, 1988, 93 : 3 - 12
  • [27] SYMMETRY DETERMINATION BY CONVERGENT-BEAM DIFFRACTION
    EADES, JA
    INSTITUTE OF PHYSICS CONFERENCE SERIES, 1988, (93): : 3 - 12
  • [28] Structure analysis of montmorillonite crystallites by convergent-beam electron diffraction
    Beermann, T
    Brockamp, O
    CLAY MINERALS, 2005, 40 (01) : 1 - 13
  • [29] MY EARLY WORK ON CONVERGENT-BEAM ELECTRON-DIFFRACTION
    MOLLENSTEDT, G
    PHYSICA STATUS SOLIDI A-APPLIED RESEARCH, 1989, 116 (01): : 13 - 22
  • [30] Use of quantitative convergent-beam electron diffraction in materials science
    Holmestad, R
    Birkeland, CR
    Marthinsen, K
    Hoier, R
    Zu, JM
    MICROSCOPY RESEARCH AND TECHNIQUE, 1999, 46 (02) : 130 - 145