From NWChem
Viewed 1244 times, With a total of 5 Posts
|
Clicked A Few Times
Threads 2
Posts 5
|
|
2:36:10 PM PDT - Mon, May 14th 2018 |
|
Dear All.
Is there any activity going on to incorporate SCAN meta-GGA functional into NWChem?
Thank you very much.
Biswajit
|
|
|
-
Niri Forum:Admin, Forum:Mod, NWChemDeveloper, bureaucrat, sysop
|
|
Forum Regular
Threads 4
Posts 209
|
|
7:11:30 AM PDT - Thu, May 24th 2018 |
|
Hi Biswajit,
We have this in the development branch. You can get this from out github link
https://github.com/nwchemgit/nwchem
to invoke it use the following in your dft block
xc scan
|
|
|
|
Clicked A Few Times
Threads 2
Posts 5
|
|
10:07:32 AM PDT - Thu, Jul 18th 2019 |
|
Hi,
Are you satisfied with the tests of the SCAN functional?
Do you have any suggestion what numerical grid should be used with SCAN?
Thank you,
Biswajit
|
|
|
-
Edoapra Forum:Admin, Forum:Mod, bureaucrat, sysop
|
|
Forum Vet
Threads 10
Posts 1632
|
|
5:32:13 PM PDT - Thu, Jul 18th 2019 |
|
Biswajit,
We have performed extensive tests on the SCAN functional.
https://github.com/nwchemgit/nwchem/issues/114
I would recommend fine (or larger: xfine, huge) grids.
BSSE correction seem to be crucial for weakly bound systems (see tests in the github issue)
|
|
|
|
Clicked A Few Times
Threads 2
Posts 5
|
|
11:07:57 AM PDT - Fri, Jul 19th 2019 |
|
Thank you.
We have been looking at water clusters. We have been using xfine grid already. We are also using large basis set aug-cc-pv5z and experience suggests that BSSE will be almost negligible with that basis for DFT. However, how BSSE affects SCAN for water I don't know. The issue we are having is that SCAN is not giving the correct ordering among few isomers of water hexamers. The energy differences are very small within 1kcal/mol. I can provide more details of our calculation if needed. We will try BSSE. Also should we write to github or this forum for further issues?
|
|
|
-
Edoapra Forum:Admin, Forum:Mod, bureaucrat, sysop
|
|
Forum Vet
Threads 10
Posts 1632
|
|
10:58:31 AM PDT - Mon, Jul 22nd 2019 |
|
Biswajit,
My suggestion is to first, compute the BSSE correction, then file a github issue.
I would also try the cc-pv5z basis (i.e. no aug-)
|
|
|
AWC's:
2.5.10 MediaWiki - Stand Alone Forum Extension
Forum theme style by: AWC