What software are you using and what do your input and output
files look like?
Jim
From:
owner-chemistry+ccl_nospam==kressworks.com[-]ccl.net
[mailto:owner-chemistry+ccl_nospam==kressworks.com[-]ccl.net] On Behalf Of
SUBHADEEP
SAHA saha.subhadeep*gmail.com
Sent: Monday, September 27, 2010 11:04 AM
To: Kress, Jim
Subject: CCL: problem with fixing a bond
Dear all,
I am trying to optimize(b3lyp/6-31g) a structure freezing almost 20 atoms and
30 bonds.Now the problem is crashing after a running number of
steps giving the following error
Iteration100 RMS(Cart)= 0.00000470 RMS(Int)= 0.01035587
New curvilinear step not converged.
Error imposing constraints
I checked the final configuration and got that the some of the groups(which are
> from the frozen bonds only,suppose I have frozen the C-H bonds of CH3 groups)
moves away from initial configuration after feeling some favorable interaction
elsewhere.
I have checked CCL archives"http://server.ccl.net/cgi-bin/ccl/message-new?2003+05+23+007".But
did not get any satisfactory solution to optimizing the structure keeping the
constrains(Whatever I have provided) same.
Can anyone please suggest a solution?
Thanks in advance...
Regards,
Subhadeep Saha
C/O Dr.Rahul Banerjee
Materials and Physical Chemistry Division
National Chemical Laboratory
Dr. Homi Bhabha Road
Pune:411008
Maharasthra
India
Ph:+91-20-2590-2387
+91-20-2590-2535
+91-20-2590-2598