Re: CCL:Gaussian Raman Intensities in Solution

Although I am not familiar with the details of the COSMO implementation in
 Gaussian,
 being the author of the original COSMO I like to shortly comment on the general
 question of Raman intensities in solution:
 Note, that high vibrational frequencies in solution are definitely not in
 equilibrium
 with the reorientational part of the solvent polarization. Therefore calculation
 of second
 derivatives of the total energy are not adequate for vibrational frequencies.
 The
 best way to calculate the Raman frequencies in solution would be
 - to first do geometry optimization in the solvent
 - then freeze the polarization charges
 - do second derivatives while treating the (molecule + frozen equilibrium
 polarization charges)
 as embedded in a medium of electronic polarizability (eps=2).
 I am not sure, whether such treatment is possible in Gaussian,
 but it efinitely would be the physically most correct way to do it.
 Andreas Klamt
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 Dr. Andreas Klamt
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 Tel.: 49-2171-73168-1  Fax: ...-9
 e-mail: andreas.klamt $#at#$ cosmologic.de
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