CCentered Lattices/CCentering  Practical Electron Microscopy and Database   An Online Book  

Microanalysis  EM Book http://www.globalsino.com/EM/  


This book (Practical Electron Microscopy and Database) is a reference for TEM and SEM students, operators, engineers, technicians, managers, and researchers.  
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There are totally three lattice types which are: Table 2962. Reflections of different lattice centerings.
As an example, the three space groups C2/m, C2 and Cm have the same systematic forbidden reflections which are caused by the Ccentering (h+k = 2n+1). The other symmetry operations in the three space groups, e.g. 2fold rotation axis (2) and mirror plane (m) in the C2/m space group, do not cause forbidden reflections. For the enlarged tetragonal unit cells, i.e. C or F centred unit cells, the symbols selected to describe the symmetry with respect to the x and y axes, and with respect to the facediagonal directions is simply the same as that selected for the equivalent P and I centred cells, but with the order of the symbols reversed e.g. the name C4/mmb is used for the enlarged unit cell of space group P4/mbm.


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The book author (Yougui Liao) welcomes your comments, suggestions, and corrections, please click here for submission. If you let book author know once you have cited this book, the brief information of your publication will appear on the “Times Cited” page.  

