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Last Update 25/ 02/ 2001
Interaction with this page may clarify the symmetry operation due to reflection plane and two fold rotation axis (or binary axis).
Initially the figure shows a crystal face pole from the north hemisphere represented in two stereographic projection diagrams, both with same coordinates. The left side will be reserved for the operation of binary axis and the right side for the reflection plane. After a click on button a the result is due to a binary axis containing the north pole (N) and the south pole (S) of the sphere and due to a reflection plane containing N and S. The graphic and literal symmetry element symbols are in red.
After a click on button b a new case with the face pole in a new position is presented. A foresight can be tried for this case if the same symmetry elements in the former orientation will be applied respectively. The actual result can be observed after a click on button c.
A click on button d shows another case, when the face pole is over S. To see the result after operation with the same symmetry element in this case, click on e.
To turn to the initial figure, click on f.
Bibliography
1. Stout, G.H. and Jensen, L.H., X-ray Structure Determination, Macmillan, London, 1972.
2. Woolfson, M.M., X-ray Crystallography, Cambridge University Press, London, 1970.
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