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According to the above definition, each symmetry operation belongs to one and only one symmetry element (not counting partial elements). The latter is determined by the geometric element of the operation. For example, we can `decompose' any site symmetry group into symmetry elements.
Example 1. A site symmetry with point group consists of: | |
and , | forming a rotoinversion axis |
and , | belonging to a rotation axis E3 |
, | belonging to a mirror plane Em. |
Example 2. Site symmetry 4/m consists of: | |
41, 42 and 43, | belonging to a rotation axis E4 |
and , | forming a rotoinversion axis |
m1, | belonging to a mirror plane Em |
, | forming a center . |
Example 3. Site symmetry 2/ consists of: | |
and 32), | belonging to four rotation axes E3 |
and ), | forming four rotoinversion axes |
, | belonging to three rotation axes E2 |
, | belonging to three mirror planes Em |
, | forming a center . |
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