Semiempirical Geometry Optimization calculation with periodic boundary condition
base... at gmail.com
Thu Nov 7 19:33:30 CET 2013
You can simply supply more SCF iterations to try to force a convergence to
solve your SCF problem. By default, MAX_SCF is 50 iterations with an
accuracy (EPS_SCF) of 1x10^-5. These parameters can simply be added to your
input file under the SCF section. Hopefully, the SCF convergence will fix
the geometry problems! I am unable to test this for you as did not provide
coordinates in the input file for your system.
On Wednesday, November 6, 2013 11:13:26 AM UTC-5, bharat wrote:
> Hello Everyone,
> I am trying to perform geometry optimization calculation using
> semiempirical methods AM1, PM3, RM1, and PM6 with periodic boundary
> condition for bulk water (64 water molecules, initial structure is from M.
> D. Ben et al. J. Phys. Chem. Lett. 4, 3753 (2013)) . It is found that SCF
> is not converged and the structures are very bad. (O-H bond lengths
> increased to 5-8 A and structure is not converged.)
> Does anyone have experience using semiempirical methods for PBC
> calculation? Please see the .xyz file using AM1 method.
> All suggestions are appreciated.
> Thank you.
> Bharat Sharma
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the CP2K-user