Subject: VIBRATIONAL FREQS

From: "E. Lewars" <[email-masked]>
Date: Wed, 30 Aug 1995 13:57:00 -0400

Ferenc Molner asked a question about the calculation of vibrational freqs and 
the role of the reduced masses.  It's my observation too that this isn't
clearly explained in the usual handy refs--they gloss over it by saying that 
the freqs are the mass-weighted eigenvalues of the hessian matrix.
  I think several people out there would appreciate it if someone, in 
answering Ferenc's question, showed in some detail how an ab in calc on a 
small molecule like, say, H-O-Cl leads to the freqs, showing the actual matrices as the rectangular
arrays they are.
Thanks
E. Lewars
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