CCL: Not able to optimize structure - bisphosphole
- From: "Daniel Morales Salazar"
- Subject: CCL: Not able to optimize structure - bisphosphole
- Date: Sat, 14 May 2016 08:49:09 -0400
Sent to CCL by: "Daniel Morales Salazar"
I am trying to optimize a molecule with the chemical formula CH52O18P4S4W2,
which contains thiophenes-phospholes, phenyl groups, and
tungsten pentacarbonyl substituents.
It is a large and especially bulky molecule. I have tried using MM and
Semi-empirical methods (PM6) unsuccessfully. The only converged trial so
far was one with the "loose" keyword using PM6, which crashed in the
following calculation with stricter parameters when I did not use the
keyword. I have tried the keywords calcfc, qc, cartesian, etc.
Any advice for these types of cases?
Semi-empirical jobs crash with the message:
"Symmetry turned off by external request.
DSYEV returned Info= 2 IAlg= 2 N= 3 NDim= 3 NE2=
Diagonalization in DiagDN failed."
MM methods crash with the message:
" Error termination request processed by link 9999."
I have the feeling that the initial geometries are not so bad even! Thank
you very much for your help.
Daniel Morales Salazar