Subject: LST in G94

From: Thorsten Koch <[email-masked]>
Date: Fri, 21 Jul 1995 10:11:26 +0200 (MST)

Dear Netters!
I have a problem using the LST-keyword in G94.
What I did is the following:
I optimized a proper structure for reactand and product. For further use 
in a LST-calculation I made sure that corresponding atoms appear in the 
same order. I used these structures as an input for the LST-calculation.

What I got was:
1. Gaussian was, all of a sudden, not able to determin orbital symmetries 
and electronic state of reactand and product. It says something like 
"partially filled degenerate orbitals" (In the previous geometry optimisation 
it had no difficulties)

2. Gaussian didn't assign all atoms of the reactand to the 
right corrosponding atoms of the product, it exchanged two atoms - which 
results in an absolutely silly guess of the transition structure. 

3. Finally, after the program attempts to scan the LST path, it aborts 
with an fortran error message: floating invalid.

So my questions are:
Are there any reasons for the difficulties handling orbital symmetry and 
electronic state?
Why doesn't Gaussian map the atoms of reactands and products onto another 
in the order given in the z-matrix? Ok, I checked it - the atoms are 
really in the order I want them to have. 
Why does the program abort when I want it to scan the LST-path?

Any hints would be appreciated.

Many thanks, Thorsten Koch

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|                        Thorsten Koch                            |
| Institut fuer physikalische Chemie II der Universitaet zu Koeln |
|                    [email-masked]                       |
|                   Tel. +49 [0]221 470 4816                      |
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