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MATERIALS SCIENCE & ENGINEERING . Part of . A Learner’s Guide. AN INTRODUCTORY E-BOOK. Anandh Subramaniam & Kantesh Balani Materials Science and Engineering (MSE) Indian Institute of Technology, Kanpur- 208016 Email: anandh@iitk.ac.in, URL: home.iitk.ac.in/~anandh.
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MATERIALS SCIENCE & ENGINEERING Part of A Learner’s Guide AN INTRODUCTORY E-BOOK Anandh Subramaniam & Kantesh Balani Materials Science and Engineering (MSE) Indian Institute of Technology, Kanpur- 208016 Email:anandh@iitk.ac.in, URL:home.iitk.ac.in/~anandh http://home.iitk.ac.in/~anandh/E-book.htm POINT GROUPS& SPACE GROUPS A Detailed Exploration Space Group diagrams and tables http://img.chem.ucl.ac.uk/sgp/mainmenu.htm Magnetic Space groups http://mpg.web.cmu.edu/
Point Groups and Space Groups: a detailed look • We have already considered an overview of point groups and space groups. • Here we have a more detailed look at various related aspects.
The 32 Point Groups Highest symmetry class is in blue The possible combinations of crystallographic symmetry operators
* The order for the highest symmetry point group for each crystal system is given. E.g. for cubic (4/m 3 2/m) point group has a order 48 → if we start with a general point then a total of 48 points is obtained
Laue groups A centrosymmetric property imparts a (pseudo) centre of symmetry to a crystal . The crystal will seem to have a centre of symmetry with respect to that property even if is actually absent = + 2 i 2/m