A Rotation Axis with Intersecting Symmetry Planes

A Rotation Axis with Intersecting Symmetry Planes 

A dot between n and m in the label n m indicates that the axis is in the plane. This combination of a rotation axis and a symmetry plane produces further symmetry planes. Their total number will be n as a consequence of the application of the -fold rotational symmetry to the symmetry plane. The complete set of symmetry operations of a figure is its symmetry group. 

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In addition to a rotation axis with intersecting symmetry planes (which is equivalent to having multiple intersecting symmetry planes), snowflakes have a perpendicular symmetry plane. This combination of symmetries is labeled m-n.m and it is characteristic of many other... 

A Rotation Axis with Intersecting Symmetry Planes and a Perpendicular Symmetry Plane... 

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