CCL:G: Hessian Matrix in Internal Coordinates
- From: Andrea Coletta <andrea_coletta**libero.it>
- Subject: CCL:G: Hessian Matrix in Internal Coordinates
- Date: Sun, 23 Nov 2008 17:33:33 +0100
Sent to CCL by: Andrea Coletta [andrea_coletta,,libero.it]
Hi, i'm trying to obtain the Hessian Matrix output in Internal
Coordinates, from a B3LYP Optimization job with Gaussian03.C02.
My route section is:
#P B3LYP/6-31G* OPT=CalcAll SCRF=CPCM
if I use this with a small molecule (e.g Water), in the log file I
find
something like:
(Enter /apps/GEN03.C02/g03/l103.exe)
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad
Berny optimization.
Internal Forces: Max 0.000010959 RMS 0.000006781
Search for a local minimum.
Step number 4 out of a maximum of 20
All quantities printed in internal units (Hartrees-Bohrs-Radians)
Second derivative matrix not updated -- analytic derivatives used.
Trust test= 1.00D+00 RLast= 3.53D-03 DXMaxT set to 4.24D-01
The second derivative matrix:
R1 R2 A1
R1 0.46509
R2 -0.00302 0.46509
A1 0.02978 0.02978 0.16989
Eigenvalues --- 0.16394 0.46802 0.46812
RFO step: Lambda= 0.00000000D+00.
and this is exactly what I want!
It works also with an HF Opt test-job I did with Glycine:
#P HF/3-21G OPT=(ModRedundant,CalcAll) SCRF=pcm
[...]
Force constants in Cartesian coordinates:
1 2 3 4 5
1 0.809587D+00
2 0.000000D+00 0.790299D+00
3 0.137405D-01 0.000000D+00 0.642144D+00
4 -0.114527D+00 0.000000D+00 -0.475510D-02 0.644272D+00
5 0.000000D+00 -0.110951D+00 0.000000D+00 0.000000D+00
0.621385D+00
6 0.118871D-01 0.000000D+00 -0.243725D+00 -0.379120D-02
0.000000D+00
[...]
Force constants in internal coordinates:
1 2 3 4 5
1 0.426378D+00
2 0.122242D-01 0.472234D+00
3 0.115444D-01 0.547739D-02 0.471563D+00
4 0.115444D-01 0.547739D-02 0.574356D-02 0.471563D+00
5 0.138575D-01 -0.102523D-02 -0.441368D-02 -0.441368D-02
0.404944D+00
6 0.737045D-02 0.195704D-03 0.204429D-03 -0.726729D-03
0.548064D-02
This is very good... the only difference is that it does'nt specify
the internal coordinate, and it wrote the Matrix just before enthering
l103.exe... rather than just after entering, like in the Water
calculation...
When I try with another molecule a little greater (33 Atoms) it
does'nt
work!!,
It does'nt print in the log the Hessian matrix, and in the fchk I find
only the Hessian Matrix in Cartesian coordinates...
I use use the same Route section, and i've tried a lot of other
combinations but nothing's working!
#P B3LYP/6-31G* OPT=CalcAll SCRF=CPCM
or
#P B3LYP/6-31G* OPT=(Redundant,CalcAll) SCRF=CPCM
or
#P B3LYP/6-31G* OPT=(ModRedundant,CalcAll) SCRF=CPCM
or
#P B3LYP/6-31G* OPT=CalcFC
etc. etc.
Maybe the problem is that my system has too many internal degree of
freedom (96)?
Any Suggestions?
Please Help me!! :-(
Thanks
*****************************
Andrea Coletta
Post-Grad. Student
University of "Tor Vergata"
Rome - Italy
*****************************