Francois, many thanks but, I am afraid, you are missing the point.
This is really a question of the limits of sqm (and possibly the level
of theory) and not one of alternative approaches... :-). When I said
"larger test set" I meant not just a few dozens but thousands of
structures.
On Thu, 8 May 2014 13:23:27 +0200
FyD <fyd.q4md-forcefieldtools.org> wrote:
> Dear Hannes,
>
> If your input structure is correct:
> i.e. no hydrogen is missing
> the total charge is correct
> the bumps are removed
> you might try a more robust code.
>
> Let's talk about Gaussian vs Gaussian as an example:
> i.e. Gaussian 03 versus Gaussian 09
> there is an important speed and SCF convergence gap between g03 and
> g09
>
> this is why we always propose the latest version of Gaussian at
> R.E.D. Server Development
> http://q4md-forcefieldtools.org/REDServer-Development/
> http://q4md-forcefieldtools.org/REDServer-Development/news.php
>
> more generally you could try to get a bunch of 50 molecules and run
> the latest version of Gaussian (vs sqm). My feeling is that there is
> no comparison; and I do not talk about the gradient value & the fact
> that sqm is a semi-empirical code...
>
> regards, Francois
>
>
> > I can't get the attached structure (sqm.in) converged. What
> > happens is that the wave function won't converge somewhere along
> > geometry optimisation, at some arbitrary step (not the first step)
> > depending on name list parameters.
> >
> > I have no particular interest in this one. The problem just came up
> > in a larger test set. The structure is ZINC03814828. Same result
> > with ZINC03814832 which is almost the same.
> >
> > The current name list is an outcome of playing around with various
> > parameters but without luck. What I wonder is if this could still
> > be made to converge or if there is a set of known structures which
> > just cannot be converged? If I replace the carboxy-ethyl group
> > with propyl the structure converges at scfconv=1.0D-9.
>
>
>
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Received on Thu May 08 2014 - 05:30:02 PDT
