Re: CCL:Wilson Out-Of-Plane Coordinate

 > 	Could someone explain me what exactly the Wilson out-of-plane
 > 	coordinate is?
 > 	I have the corresponding reference
 > 	Wilson, E. B.; Decius, J. C.; Cross, P. C. Molecular Vibrations,
 > 	Dover, New York (1980).
 > 	but we don't have the book here.
    Another reference, which may be very helpful, is
    S. Califano: Vibrational States, J. Wiley & Sons, London (1976)
    ISBN 0-471-12996-8 (there may be a new edition of this useful book)
    Chapter 4 of this book deals with the Wilson internal coordinates.
    Sometimes the out-plane bend coordinate is also defined as "impromper
    torsion" which involves the dihedral angle between two adjoining planes.
    The difference between the two definitions is, however, insignificant for
    an (almost) planar configuration.
 !  Tom Sundius, Dept. of Physics   Internet: Tom.Sundius %! at !%
 !  University of Helsinki, Finland          sundius %! at !%