[DFTB-Plus-User] iterated process of MD jobs

Bálint Aradi aradi at uni-bremen.de
Mon Nov 18 12:06:15 CET 2019

Dear Young,

> 1. Can I generate a file of last atomic velocities (similarly to
> geo_end.gen for the position) after completion of a MD work, so that I
> can insert it in the input of new work?

Yes, currently the velocities are stored in the xyz geometry file in
columns 6 - 8. Those you can use to restart your calculation. They are,
however, in AA/ps, so make sure to specify the units of the velocities
in the DFTB+ input accordingly!

> 2. For parallel running (4 prcoesses) of "mpirun -np 4 -machinefile
> $PBS_NODEFILE dftb+", do I have to explicitly describe group = 4 (not 1)
> in Parallel section?

Groups only make sense, if you wan't to parallelise over k-points. (One
group deals with one k-point at a time). If you do not specify groups,
all processes will work on the same Hamiltonian.

Rule of thumb: If you have a small Hamiltonian but many k-points, it may
make sense. If you don't have k-points, it does not.

> What output file will be created for periodic saving (for
> MDRestartFrequecy) of cooridnates, velocties, charges of atoms?

The xyz geometry file.

  Best regards,


Dr. Bálint Aradi
Bremen Center for Computational Materials Science, University of Bremen

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: OpenPGP digital signature
URL: <http://mailman.zfn.uni-bremen.de/pipermail/dftb-plus-user/attachments/20191118/de42c385/attachment.sig>

More information about the DFTB-Plus-User mailing list