From chemistry-request@ccl.net Tue Jun 25 11:42:21 1991
Date: Tue, 25 Jun 91 10:16 CST
From: Andy Holder <AHOLDER@VAX1.UMKC.EDU>
Subject: Force Constant Calculations
To: CHEMISTRY@ccl.net
Status: R

Performing force constant calculations on a molecule as small as
  benzene is a relatively simple task with a high quality semi-
  empirical method such as AM1.  The results are also in pretty
  good agreement with experiment.  Whether this will get you what
  need depends on the level of accuracy that you require of the
  numbers.  There is no simple scaling factor for empirical adjust-
  ments as is the case with ab initio methods, but the frequencies
  from these type of calculations are generally good to +- 5-10%.

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                              DR. ANDREW HOLDER

Department of Chemistry              ||  BITNET Addr:   AHOLDER@UMKCVAX1
University of Missouri - Kansas City ||  Internet Addr: aholder@vax1.umkc.edu
Kansas City, Missouri 64110          ||  Phone Number:  (816) 235-2293
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