Subject: geometry optimizations using oniom

From: [email-masked]
Date: Tue, 14 Sep 1999 10:49:52 +0200

Hi everybody

I have had some problems performing geometry optimizations using the 
oniom method i gaussian 98.

I work with a  metallo enzyme.
The nearest parts of the coordinating amino acid residues and the metal ion are 
treated on b3lyp level, whereas pm3 is used for the rest. I freeze the alpha
carbons of the aminoacids next to the coordinating aminoacid residues relative 
to each other to mimic the restriction that the backbone put on the active site. 

One of the calculations seemed to work fine. It ran about 35 cycles. I then 
restarted it from cycle nr 24, because it had the smallest forces, and 
all of a sudden I got the error message : 

 Incomplete coordinate system.  Try restarting with
 Geom=Check Guess=Read Opt=(ReadFC,NewRedundant)
 Incomplete coordinate system.
 Error termination via Lnk1e in /usr/local/g98/l103.exe.

Sometimes I have also had this message already after the first cycle.  

What does this message mean? Is there any way you can avoid this error?

Best regards

Lars

PS My e-mail address is : [email-masked]