1
|
Abstract
![]()
Electron crystallography
has a storied history which rivals that
of its more established X-ray-enabled counterpart. Recent advances
in data collection and analysis have sparked a renaissance in the
field, opening a new chapter for this venerable technique. Burgeoning
interest in electron crystallography has spawned innovative methods
described by various interchangeable labels (3D ED, MicroED, cRED,
etc.). This Review covers concepts and findings relevant to the practicing
crystallographer, with an emphasis on experiments aimed at using electron
diffraction to elucidate the atomic structure of three-dimensional
molecular crystals.
Collapse
Affiliation(s)
- Ambarneil Saha
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, Los Angeles, California 90095, United States.,Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - Shervin S Nia
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, Los Angeles, California 90095, United States.,Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - José A Rodríguez
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, Los Angeles, California 90095, United States.,Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095, United States
| |
Collapse
|
2
|
Ershov DS, Besprozvannykh NV, Sinel’shchikova OY. Synthesis and Photocatalytic and Electrophysical Properties of Ceramic Materials in the PbO–Bi2O3–Fe2O3 System. RUSS J INORG CHEM+ 2022. [DOI: 10.1134/s003602362201003x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
3
|
Gemmi M, Lanza AE. 3D electron diffraction techniques. ACTA CRYSTALLOGRAPHICA SECTION B, STRUCTURAL SCIENCE, CRYSTAL ENGINEERING AND MATERIALS 2019; 75:495-504. [PMID: 32830707 DOI: 10.1107/s2052520619007510] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 05/23/2019] [Indexed: 06/11/2023]
Abstract
3D electron diffraction is an emerging technique for the structural analysis of nanocrystals. The challenges that 3D electron diffraction has to face for providing reliable data for structure solution and the different ways of overcoming these challenges are described. The route from zone axis patterns towards 3D electron diffraction techniques such as precession-assisted electron diffraction tomography, rotation electron diffraction and continuous rotation is also discussed. Finally, the advantages of the new hybrid detectors with high sensitivity and fast readout are demonstrated with a proof of concept experiment of continuous rotation electron diffraction on a natrolite nanocrystal.
Collapse
Affiliation(s)
- Mauro Gemmi
- Center for Nanotechnology Innovation@NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, Pisa, 56127, Italy
| | - Arianna E Lanza
- Center for Nanotechnology Innovation@NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, Pisa, 56127, Italy
| |
Collapse
|
4
|
Meshi L, Samuha S. Characterization of Atomic Structures of Nanosized Intermetallic Compounds Using Electron Diffraction Methods. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1706704. [PMID: 29602209 DOI: 10.1002/adma.201706704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 12/28/2017] [Indexed: 06/08/2023]
Abstract
In metallurgy, many intermetallic compounds crystallize as nanosized particles in metallic matrices. These particles influence dramatically the physical properties of engineering materials such as alloys and steels. Since properties and crystal structure are intimately linked, characterization of the atomic model of these intermetallides is crucial for the development of new alloys. However, this structural information usually cannot be attained using traditional X-ray diffraction methods, limited by the small volume and size of the precipitates. In these cases, electron diffraction (ED) is the most suitable method. In the last few decades, ED has experienced a tremendous leap forward. Many structures, including intermetallides, are solved using these methods. The class of intermetallides should be discussed independently since these phases do not comprise regular polyhedrals; moreover, the interatomic distances and angles vary drastically even in the same compositional system. These facts point to difficulties that have to be overcome during the solution path. Furthermore, intermetallic compounds can be of high complexity-possessing hundreds of atoms in the unit cell. Here, this topic is expanded with an emphasis on novel developments in the field.
Collapse
Affiliation(s)
- Louisa Meshi
- Department of Materials Engineering, Ben Gurion University of the Negev, Beer-Sheva, 84105, Israel
| | - Shmuel Samuha
- Department of Materials, Nuclear Research Center Negev (NRCN), P.O. Box 9001, Beer-Sheva, 84190, Israel
| |
Collapse
|
5
|
Single-crystal analysis of nanodomains by electron diffraction tomography: mineralogy at the order-disorder borderline. ACTA ACUST UNITED AC 2018. [DOI: 10.1515/zkri-2017-2130] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Electron diffraction tomography is a powerful emerging method for the structure characterization of materials available only as sub-micrometric grains. This technique can in fact deliver complete 3D information from a single crystal of few hundreds or few tens of nanometers, allowing the analysis of polyphasic or polytypic mixtures that generally cannot be fully addressed by X-ray methods. In this paper, we report and discuss three mineralogy-related study cases where electron diffraction tomography was the only way for achieving a proper description of the sample, by the identification and the structure determination of all the phases or all the polytypes within. We also show how electron diffraction tomography and dynamical refinement can be combined for finding accurate atomic positions and localizing hydrogen atoms at room conditions. Finally, we stress the future potential of this method in the fields of mineralogy and experimental petrology, where till now many samples cannot be properly described because nanocrystalline, polyphasic or disordered. Electron diffraction tomography can be used for detecting unexpected or unknown phases in high-pressure synthetic yields or for the characterization of fine rocks formed under extreme conditions, like impactites or meteorites. Eventually, this method allows the structure characterization of single domains that are ordered only at the scale of few cell repetitions, and therefore it makes possible investigating those materials at the borderline between crystalline and amorphous matter and delivers crucial and unique elements for the understanding of the first stages of solid matter organization.
Collapse
|
6
|
Weirich TE. The crystal structure of Zr2Se reinvestigated by electron crystallography and X-ray powder diffraction. CRYSTALLOGR REP+ 2018. [DOI: 10.1134/1.1756636] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
7
|
Weirich TE. Electron diffraction structure analysis: structural research with low-quality diffraction data. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zkri.218.4.269.20744] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Electron Diffraction Structure Analysis (EDSA) with data from standard selected-area electron diffraction (SAED) is still the method of choice for structure determination of nano-sized single crystals. The recently determined heavy atom structure α-Ti2Se (Albe & Weirich, 2003) is used as an example to illustrate the developed procedure for structure determination from two-dimensionally SAED data via direct methods and kinematical least-squares refinement. Despite the investigated crystallite had a relatively large effective thickness of about 230 Å as determined from dynamical calculations, the obtained structural model from SAED data was found in good agreement with the result from an earlier single crystal X-ray study (Weirich, Pöttgen & Simon, 1996). Arguments, which support the validity of the used quasi-kinematical approach, are given in the text. The influences of dynamical and secondary scattering on the quality of the data and the structure solution are discussed. Moreover, the usefulness of first-principles calculations for verifying the results from EDSA is demonstrated by two examples, whereas one of the structures was unattainable by conventional X-ray diffraction.
Collapse
|
8
|
Boulahya K, Ruiz-González L, Parras M, González-Calbet JM, Nickolsky MS, Nicolopoulos S. Ab initio determination of heavy oxide perovskite related structures from precession electron diffraction data. Ultramicroscopy 2007; 107:445-52. [PMID: 17254714 DOI: 10.1016/j.ultramic.2006.03.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2005] [Accepted: 03/23/2006] [Indexed: 11/22/2022]
Abstract
Two complex perovskite-related structures were solved by ab initio from precession electron diffraction intensities. Structure models were firstly derived from HREM images and than have been confirmed independently using two and three-dimensional sets of precession intensities. Patterson techniques prove to be effective for ab initio structure resolution, specially in case of projections with no overlapping atoms. Quality of precession intensity data may be suitable enough to resolve unknown heavy oxide structures.
Collapse
Affiliation(s)
- Khalid Boulahya
- Dpto. Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, E28040 Madrid, Spain
| | | | | | | | | | | |
Collapse
|
9
|
Gemmi M, Nicolopoulos S. Structure solution with three-dimensional sets of precessed electron diffraction intensities. Ultramicroscopy 2007; 107:483-94. [DOI: 10.1016/j.ultramic.2006.03.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2006] [Accepted: 03/09/2006] [Indexed: 11/24/2022]
|
10
|
Weirich TE, Portillo J, Cox G, Hibst H, Nicolopoulos S. Ab initio determination of the framework structure of the heavy-metal oxide CsxNb2.54W2.46O14 from 100kV precession electron diffraction data. Ultramicroscopy 2006; 106:164-75. [PMID: 16137828 DOI: 10.1016/j.ultramic.2005.07.002] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2004] [Revised: 07/06/2005] [Accepted: 07/08/2005] [Indexed: 11/17/2022]
Abstract
The present work deals with the ab initio determination of the heavy metal framework in Cs(x)(Nb, W)(5)O(14) from precession electron diffraction intensities. The target structure was first discovered by Lundberg and Sundberg [Ultramicroscopy 52 (1993) 429-435], who succeeded in deriving a tentative structural model from high-resolution electron microsopy (HREM) images. The metal framework of the compound was solved in this investigation via direct methods from hk0 precession electron diffraction intensities recorded with a Philips EM400 at 100 kV. A subsequent (kinematical) least-squares refinement with electron intensities yielded slightly improved co-ordinates for the 11 heavy atoms in the structure. Chemical analysis of several crystallites by EDX is in agreement with the formula Cs(0.44)Nb(2.54)W(2.46)O(14). Moreover, the structure was independently determined by Rietveld refinement from X-ray powder data obtained from a multi-phasic sample. The compound crystallises in the orthorhombic space group Pbam with refined lattice parameters a=27.145(2), b=21.603(2), and c=3.9463(3)A. Comparison of the framework structure from electron diffraction with the result from Rietveld refinement shows an average agreement for the heavy atoms within 0.09 A.
Collapse
Affiliation(s)
- Thomas E Weirich
- Gemeinschaftslabor für Elektronenmikroskopie der Rheinisch-Westfälischen Technischen Hochschule (RWTH) Aachen, Ahornstrasse 55, Aachen D-52074, Germany.
| | | | | | | | | |
Collapse
|
11
|
Abstract
Among different techniques, electron crystallography presents the advantage to determine structures on a local scale or from very small samples. Different methods such as image processing, exit wave reconstruction, Patterson analysis, or direct methods can be applied for getting a starting structural model. Results obtained on various oxides have shown that the dynamical nature of electron scattering, far from being detrimental, can even help in the localization of oxygen atoms close to heavier scatters. Concerning the structure refinement step, it is now possible to introduce dynamical effect correction through multislice calculations combined with least-squares refinement. However, depending on the problem to solve and the accuracy needed, the alternative solution consisting in getting as close as possible to kinematical conditions is still worth considering. Different examples of structures refined from electron diffraction data are given.
Collapse
|