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What is the default radial grid for DFT in DALTON?

Posted: 21 Jul 2015, 09:10
by rob
Hi all,
I've been trying to compare some PSI4 DFT calculations with DALTON results.
From the DALTON manual is extremely clear how to modify all the radial and angular grid parameters (page 272, under the "*DFT INPUT" section)
However, the default radial grid and default partitioning scheme are not specified. The information on the grid generation strategy (both radial and angular)
is also nowhere to be found within the output file.
So, as from the subject: What is the default radial grid for DFT in DALTON?
Also, how many radial points are used in the radial grid when .RADINT has its default value of 1.0e-13?
Thanks a lot in advance!

Re: What is the default radial grid for DFT in DALTON?

Posted: 21 Jul 2015, 09:23
by bast
dear Roberto,

this is the radial grid in DIRAC and AFAIK also the default
in Dalton (i think there are several options within Dalton):
http://dx.doi.org/10.1007/s002140100263

the radial grid is basis dependent so the number of points not only
depends on the parameter but also on the basis set range and angular momentum.
in other words if you add steep or diffuse functions you will get more points.

the partitioning is AFAIK this one: http://dx.doi.org/10.1063/1.454033

i have implemented a standalone lib for numerical grids:
https://github.com/bast/numgrid
i am not meaning to place a shameless plug here but it may be clearer
from that code what is going on since it is isolated.
it uses the above mentioned radial and partitioning schemes.
the other thing that you could do is to plug it into Psi4 and hopefully
get exactly the Dalton grid (the lib has a Python interface).

good luck!
radovan