Subject: CCL:solvating using gaussian98

From: "Jens Spanget-Larsen" <[email-masked]>
Date: Sat, 15 Mar 2003 00:03:11 +0100

Dear Ian:

> I am using GaussianW98
> I am trying to solvate a molecule in a liquid other than the ones
> described in the manual with the following input line
> 
> # opt=tight hf/sto-3g* scrf=(pcm,dielectric=34.9) geom=connectivity
> 
> It seem to ignore the dielectric value and reverts to water. Iam
> doing something wrong here I know but I cant see it.
> . . . .

Yeah, this is annoying! I never succeeded in making this work with 
G98 (it was no problem with G94). I gave up and switched to IPCM. 
This is a somewhat more sophisticated SCRF-model where the 
solute/solvent boundary is defined as an electronic isodensity 
surface, allowed to relax in the solvent field. A job like the 
following, specifying, say, dielectric constant = 10 and isodensity = 
0.001, will work. You may adjust the isodensity value to suit your 
problem.

----------------------------------------------------------
%chk=chryzrad
#t B3LYP/EPR-II IPCM SCF=Tight Guess=Read Geom=Check test

Chrysazin Radical Anion (eps=10, IsoDensity=0.001)

   -1   2

10  0.001
----------------------------------------------------------

Yours, Jens >--<

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JENS SPANGET-LARSEN         Office:         +45 4674 2710
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