LJ to semi-empirical

[ivan]

Hi Axel,

thanks for your help. i would prefer a pure semi-empirical simulation,
rather than a hybrid run. it's not clear to me if AM1 or PM3 can be
used with some kind of stochastic boundary conditions (or anything
else, that simulates a thermostat), or not. Are they only suitable for
gas-phase calculations at present stage?

regards
ivan

On szept. 13, 18:16, Axel <akoh... at gmail.com> wrote:
> hi ivan,
>
> how about just taking a large classical TIP3P water box
> and doing a QM/MM run with a large AM1 box/cluster in it?
> thanks to teo's recent efforts SE-QM/MM seems to be
> working fine now. that may not get you all the way, but
> i am certain that it would still be worth investigating it.
> please contact me at akoh... at cmm.chem.upenn.edu, if you
> want to discuss in more detail.
>
> cheers,
>    axel.
>
> On Sep 13, 6:54 am, ivan <solt... at yahoo.com> wrote:
>
> > Hi Teo and Juerg
>
> > thanks for the quick reply. Actually, i'm absolutely new at CP2K (i've
> > downloaded the code only a few days ago), so i don't have a working
> > input yet. If i can't create it pretty soon, i will show up here
> > again.. This option sounds great
> > for me, but if (as Juerg warned me in his meassage) AM1 can not be
> > used with a periodic boundary, i'm a little lost again. Thanks anyway
>
> > regards
> > ivan
>
> > On szept. 13, 12:43, Juerg Hutter <hut... at pci.uzh.ch> wrote:
>
> > > Hi
>
> > > I just wanted to add that currently periodic boundary
> > > conditions cannot be used with the NDDO (AM1, PM3 etc)
> > > models in cp2k.
>
> > > regards
>
> > > Juerg
>
> > > ----------------------------------------------------------
> > > Juerg Hutter                   Phone : ++41 44 635 4491
> > > Physical Chemistry Institute   FAX   : ++41 44 635 6838
> > > University of Zurich           E-mail: hut... at pci.uzh.ch
> > > Winterthurerstrasse 190
> > > CH-8057 Zurich, Switzerland
> > > ----------------------------------------------------------
>
> > > On Thu, 13 Sep 2007, ivan wrote:
>
> > > > Dear All,
>
> > > > i am trying to reproduce the diffusivity (and g(r)) of a classical
> > > > water model (TIP3P) with semi-empirical water (probably AM1, might be
> > > > PM3). For this aim, i would like to add an artificially tuned Lennard-
> > > > Jones term to the AM1 energy. Where do you think i should touch the
> > > > cp2k code to do that? Many thanks in advance for any idea
>
> > > > regards
> > > > ivan