Bond Stretching / Bending Force Constants for IR

[Dave <TILBROOK $#at#$ chem.surrey.ac.uk>]

 To anybody who may be able to help.
 I am justing starting to work on a project which is aiming to simulate the
 IR spectra of organic polymers. The software I am using does this by a
 normal mode calculation. The problem which I am encountering is that
 the parameter set which I am using (Dreiding II) does not  have
 accurate values for the bond stretching and bending force constants
 and thus does not give us good enough results.
 Does anybody know of a source of force constants for these bonds on
 the net? or do they know of any places that I can find extensive IR
 band absorption tables. At present my sole source of data is my Aldrich
 IR catalogue and a few simple IR spectroscopy books which give the
 wavenumber for the stretch or bend which I can use to calculate the
 force constant.
 Thanks in advance to anybody that can help me
 Regards
 Dave Tilbrook
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 David Tilbrook              *   Tel: 44 483 300 800 x 2632
 Polymer Group,              *                       x 2617
 Chemistry Department,       *
 University of Surrey,       *   Fax: 44 483 300 803
 Guildford, Surrey, GU2 5XH  *
 U.K.                        *
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