Zou Xiaodong, Hovmöller Sven
Structural Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden.
Acta Crystallogr A. 2008 Jan;64(Pt 1):149-60. doi: 10.1107/S0108767307060084. Epub 2007 Dec 21.
The study of crystals at atomic level by electrons - electron crystallography - is an important complement to X-ray crystallography. There are two main advantages of structure determinations by electron crystallography compared to X-ray diffraction: (i) crystals millions of times smaller than those needed for X-ray diffraction can be studied and (ii) the phases of the crystallographic structure factors, which are lost in X-ray diffraction, are present in transmission-electron-microscopy (TEM) images. In this paper, some recent developments of electron crystallography and its applications, mainly on inorganic crystals, are shown. Crystal structures can be solved to atomic resolution in two dimensions as well as in three dimensions from both TEM images and electron diffraction. Different techniques developed for electron crystallography, including three-dimensional reconstruction, the electron precession technique and ultrafast electron crystallography, are reviewed. Examples of electron-crystallography applications are given. There is in principle no limitation to the complexity of the structures that can be solved by electron crystallography.
通过电子在原子水平上对晶体进行研究——电子晶体学——是对X射线晶体学的重要补充。与X射线衍射相比，电子晶体学确定结构有两个主要优点：（i）可以研究比X射线衍射所需晶体小数百万倍的晶体，以及（ii）晶体学结构因子的相位在X射线衍射中丢失，但在透射电子显微镜（TEM）图像中存在。本文展示了电子晶体学的一些最新进展及其应用，主要是在无机晶体方面。从TEM图像和电子衍射中都可以将晶体结构解析到二维和三维的原子分辨率。综述了为电子晶体学开发的不同技术，包括三维重建、电子进动技术和超快电子晶体学。给出了电子晶体学应用的实例。原则上，电子晶体学能够解析的结构复杂性没有限制。
