X-ray diffraction using focused-ion-beam-prepared single crystals
X-ray diffraction using focused-ion-beam-prepared single crystals
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使用聚焦离子束制备的单晶进行 X 射线衍射
DOI：
10.1107/s1600576720003143
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发表时间：
2020
影响因子：
6.1
通讯作者：
D. C. Meyer
中科院分区：
文献类型：
--
作者：
T. Weigel;C. Funke;M. Zschornak;T. Behm;H. Stöcker;T. Leisegang;D. C. Meyer
高质量的单晶X射线衍射测量是获得精确可靠的结构数据和电子密度的先决条件。因此，单晶应满足几个条件，其中规则的限定形状对于由具有高X射线吸收系数的重元素组成的化合物特别重要。通过50 μ m厚的LiNbO 3晶体的X射线的吸收会使Mo Kα辐射的透射率降低几十个百分点，这使得有必要对反射强度进行吸收校正。 为了减少关于晶体形状的模糊性，用于必要的吸收校正，提出并评价了一种从大样品中制备规则形状单晶的方法。该方法利用聚焦离子束以可重复且仔细地切割具有限定尺寸和形状的晶体而不分裂。为了评估，单晶X-射线衍射研究，使用实验室衍射仪，比较不同制备的铌酸锂晶体源自相同的宏观晶体板。数据简化，结构细化和电子密度重建的结果表明，所有制备的晶体定性相似的值。因此，不同制备技术的影响小于预期。然而，原子坐标，电子密度和原子电荷应该是更可靠的，因为聚焦离子束制备的晶体表现出最小的消光影响。这种制备技术特别推荐用于敏感样品、需要微创制备程序的情况以及从特定区域制备晶体、复杂材料结构和无法用常规方法（破碎或研磨）制备的材料。
High-quality single-crystal X-ray diffraction measurements are a prerequisite for obtaining precise and reliable structure data and electron densities. The single crystal should therefore fulfill several conditions, of which a regular defined shape is of particularly high importance for compounds consisting of heavy elements with high X-ray absorption coefficients. The absorption of X-rays passing through a 50 µm-thick LiNbO3 crystal can reduce the transmission of Mo Kα radiation by several tens of percent, which makes an absorption correction of the reflection intensities necessary. In order to reduce ambiguities concerning the shape of a crystal, used for the necessary absorption correction, a method for preparation of regularly shaped single crystals out of large samples is presented and evaluated. This method utilizes a focused ion beam to cut crystals with defined size and shape reproducibly and carefully without splintering. For evaluation, a single-crystal X-ray diffraction study using a laboratory diffractometer is presented, comparing differently prepared LiNbO3 crystals originating from the same macroscopic crystal plate. Results of the data reduction, structure refinement and electron density reconstruction indicate qualitatively similar values for all prepared crystals. Thus, the different preparation techniques have a smaller impact than expected. However, the atomic coordinates, electron densities and atomic charges are supposed to be more reliable since the focused-ion-beam-prepared crystal exhibits the smallest extinction influences. This preparation technique is especially recommended for susceptible samples, for cases where a minimal invasive preparation procedure is needed, and for the preparation of crystals from specific areas, complex material architectures and materials that cannot be prepared with common methods (breaking or grinding).
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环境参数变化对 X 射线束强度的影响：随时间变化的吸收校正
影响因子：
6.1
作者：
T. Weigel;T. Leisegang;M. Zschornak;M. Herrmann;M. Rothenberger;Andreas Wünsche;H. Stöcker;D. Meyer
通讯作者：
D. Meyer
伦结构分析的理论与实践
DOI：
10.1007/978-3-663-06828-0
发表时间：
1975
期刊：
Acta crystallographica. Section A, Foundations of crystallography
影响因子：
--
作者：
E. Wölfel
通讯作者：
E. Wölfel
聚焦离子束铣削：一种用于地球和行星材料微量分析的特定位点样品提取方法
影响因子：
3.1
作者：
P. Heaney;E. Vicenzi;L. Giannuzzi;K. Livi
通讯作者：
K. Livi
使用聚焦离子束从汉福德土壤中提取含钚微晶进行单晶 X 射线衍射分析
影响因子：
6.1
作者：
J. Corbey;Dallas D. Reilly;L. Sweet;T. Lach
通讯作者：
T. Lach
DOI：
--
发表时间：
2007
期刊：
--
影响因子：
--
作者：
Weilie Zhou;Z. Wang
通讯作者：
Weilie Zhou;Z. Wang