Point Group -42m Versus -4m2

The first point-group diagram below shows the arrangment of the symmetry elements for point group -42m:

Point Group -42m

The next point-group diagram shows the arrangment of the symmetry elements for point group -4m2:

Point Group -4m2

The only significant difference between these two figures is that the second figure is rotated by 45° about an axis perpendicular to the plane of the screen with respect to the first one. In both cases the number and arrangement of symmetry elements is identical. For each figure, the point-group nomenclature is based on conventional XY screen directions, i.e. X horizontal and Y vertical.


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© Copyright 1997-2006.  Birkbeck College, University of London. Author(s): Jeremy Karl Cockcroft