SCAN meta-GGA functional

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3:36:10 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

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8:11:30 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

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11:07:32 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

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6:32:13 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)

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12:07:57 PM 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?

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11:58:31 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-)

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