This applet models the symmetry operations of the group D7h. Click on the C1 box to see the animation for the operation, a 360 degree rotation (which is equivalent to the identity operation).
There is one C2, a 2-fold (180 degree) rotation.
C7 is a 7-fold rotation in the clockwise direction, and C72 represents two consecutive C7's..
The letter σ represents a mirror plane, which reflects one part of the molecular into the other half. σh is the horizontal mirror plane, in the plane of the screen - it reflects the top half of each atom into its bottom half. σv is the vertical mirror plane, perpendicular to the plane of the computer screen. It reflects the right half of the pentagon into the left, reflecting the right half of atom 1 into the left half of 1. Yellow color is used to suggest a reflective glass.
There are also S7 rotation axes in the group D7h; no animation for it has yet been added to the applet.
A classic example of this group is the tropyllium cation.
© 2003-2011 by Lawrence T. Sein. All rights reserved.
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