Subject: PCM Geometry Optimization

From: val <[email-masked]>
Date: Mon, 03 May 1999 16:43:17 +0400

Dear CCL'ers,

I have some problems with PCM geometry optimization of transition
metal complexes (ECP bases set) in GAMESS program. First 5 or 6 
steps it goes like a normal geometry optimization, but during all
the rest cycles gradient doesn't change leading to unconverged 
geometry search (an example attached below).

Does anybody know how to solve the problem (or just a hint ;) ?

It would be nice to hear if anybody were successful in obtaining 
PCM geometries of TM complexes with other programs.
In addition, any references concerning PCM calculations on platinum
group metal complexes are very appreciated. It is of interest whether 
PCM optimization is a problem of the particular software or a general 
one.

Thanks!

The summary will be sent.

best regards,
Valentin.

       PCM geometry optimization example:

step=1    MAXIMUM GRADIENT =  0.0029642    RMS GRADIENT = 0.0010251
step=2    MAXIMUM GRADIENT =  0.0020712    RMS GRADIENT = 0.0006788
step=3    MAXIMUM GRADIENT =  0.0014879    RMS GRADIENT = 0.0005576
step=4    MAXIMUM GRADIENT =  0.0007580    RMS GRADIENT = 0.0003812
step=5    MAXIMUM GRADIENT =  0.0004269    RMS GRADIENT = 0.0001639

step=6    MAXIMUM GRADIENT =  0.0001744    RMS GRADIENT = 0.0000857
step=7    MAXIMUM GRADIENT =  0.0001727    RMS GRADIENT = 0.0000677
step=8    MAXIMUM GRADIENT =  0.0001685    RMS GRADIENT = 0.0000617
step=9    MAXIMUM GRADIENT =  0.0001604    RMS GRADIENT = 0.0000706
step=10   MAXIMUM GRADIENT =  0.0001525    RMS GRADIENT = 0.0000608
step=11   MAXIMUM GRADIENT =  0.0001546    RMS GRADIENT = 0.0000611

...................

step=60    MAXIMUM GRADIENT =  0.0001495    RMS GRADIENT = 0.0000628
step=61    MAXIMUM GRADIENT =  0.0001502    RMS GRADIENT = 0.0000598
step=62    MAXIMUM GRADIENT =  0.0001495    RMS GRADIENT = 0.0000592
step=63    MAXIMUM GRADIENT =  0.0001533    RMS GRADIENT = 0.0000718
step=64    MAXIMUM GRADIENT =  0.0001493    RMS GRADIENT = 0.0000593

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