THE DIHEDRAL ANGLE

Definition: The angle created by two intersecting planes

In the illustration above, A and B are two separate planes lying perpendicular to another plane C. The dihedral angle equals zero between planes A and B.

To demonstrate a dihedral angle greater than zero, first let a_A and a_B equal 90 degrees. Second, let plane B rotate around the line where plane B and C intersect while letting plane A remain perpendicular to C. For example, let a_B (the angle where plane B intersects plane C) equal 60 degrees.

The dihedral angle (represented by the symbol J) between A and B now equals 30 degrees. This can also be viewed as the illustration below.

QUESTION

If a dihedral angle exists between two intersecting planes, then what is the dihedral angle between plane A and C? CLICK HERE FOR THE ANSWER

MOVE ONTO SEEING DIHEDRAL ANGLES IN THE ETHANE MOLECULE

Bryan Modders
with Dr. Abby Parrill 
Department of Chemistry
Michigan State University

These pages may be downloaded and linked from other pages freely for academic
and educational purposes. Questions, problems, and errors should be sent to parrill@argus.cem.msu.edu