Hi Francois,
I am going to run a few calculations with k-points on the WO3 surface. I am wondering if there is any specific kind of parallelism implemented in Qbox that I can exploit for calculations with k-points (something similar to pools in Quantum-ESPRESSO).
Thank you
Best,
Matteo
Calculations with k-points
Forum rules
You must be a registered user to post in this forum. Registered users may also post new topics if they consider that their subject does not correspond to any topic already present on the forum.
You must be a registered user to post in this forum. Registered users may also post new topics if they consider that their subject does not correspond to any topic already present on the forum.
-
fgygi
- Site Admin
- Posts: 167
- Joined: Tue Jun 17, 2008 7:03 pm
Re: Calculations with k-points
Hi Matteo,
Currently there is no parallelism on k-points, since the focus is mostly on large-cell gamma point MD simulations. If you use k-points, make sure to specify all equivalent k-points (except for k, -k symmetry which is included in all algorithms by default). So for a slab calculations, you could use:
kpoint delete 0 0 0
kpoint add 0.25 -0.25 0.00 0.500000
kpoint add 0.25 0.25 0.00 0.500000
The first "kpoint delete" command is used to remove the (default) k=0 point.
The two k-points added then give you the equivalent of a 2x2x1 grid.
Note that this should only done in the first calculation when defining the system. The restart files then contain all the k-point information and the load command reads it accordingly.
You can use the program kpgen (in util/kpgen/kpgen.C) to generate other grids.
Francois
Currently there is no parallelism on k-points, since the focus is mostly on large-cell gamma point MD simulations. If you use k-points, make sure to specify all equivalent k-points (except for k, -k symmetry which is included in all algorithms by default). So for a slab calculations, you could use:
kpoint delete 0 0 0
kpoint add 0.25 -0.25 0.00 0.500000
kpoint add 0.25 0.25 0.00 0.500000
The first "kpoint delete" command is used to remove the (default) k=0 point.
The two k-points added then give you the equivalent of a 2x2x1 grid.
Note that this should only done in the first calculation when defining the system. The restart files then contain all the k-point information and the load command reads it accordingly.
You can use the program kpgen (in util/kpgen/kpgen.C) to generate other grids.
Francois