On Tue, 2008-05-13 at 20:32 +0300, Jussi Lehtola wrote:
> On Tue, 2008-05-13 at 14:34 +0100, Kukol, Andreas wrote:
> > First try the EM/MD of 1 molecule in vacuum ('ethanol-gas') and check, if 
> > it looks reasonable.
> > 
> Thanks, using the vacuum method I seem to get better results.

It seems I spoke too soon. Energy minimising the one-particle structure
in vacuum gives me the following potential energies:

methanol        21.4
ethanol         9.4
propanol        3.8
butanol         4.1
pentanol        12.2
hexanol         81.0

All minimizations have converged with Fmax < 1e-3. Are these energies
reasonable? The energies of methanol and hexanol are somewhat high.

Energy minimisation with a system of 4913 methanol molecules with
initial density of 500 kg/m^3 and periodic boundary conditions gives as
potential energy Epot = -1.67e5, however the forces do not converge. 
Running the system with Berendsen pressure and temperature thermostats
(p = 1 bar, T = 300 K) results in a crash after 82 ps. The total energy
is positive and of the order 1e5.
-- 
------------------------------------------------------
Jussi Lehtola, FM, Tohtorikoulutettava
Fysiikan laitos, Helsingin Yliopisto
[EMAIL PROTECTED], p. 191 50673
------------------------------------------------------
Mr. Jussi Lehtola, M. Sc., Doctoral Student
Department of Physics, University of Helsinki, Finland
[EMAIL PROTECTED]
------------------------------------------------------

_______________________________________________
gmx-users mailing list    gmx-users@gromacs.org
http://www.gromacs.org/mailman/listinfo/gmx-users
Please search the archive at http://www.gromacs.org/search before posting!
Please don't post (un)subscribe requests to the list. Use the 
www interface or send it to [EMAIL PROTECTED]
Can't post? Read http://www.gromacs.org/mailing_lists/users.php

Reply via email to