[DFTB-Plus-User] Failture in GetMaxGDispersion

[Bálint Aradi]

Dear Richie,

> I looked into the source code and found out that the function
> getMaxGDispersion(eta, c6sum, minValue) result(xx) gives this error when
> (yy > minValue .and. xx <= huge(1.0_dp)) is never fulfilled.
> But I cannot get a direct logical connection to my input.

Your problem is the very asymmetrical unit cell: only ca. 2 Angstrom
wide in lateral direction, but over 1000 (!) Angstrom in height. This
causes problems for the Ewald-like summation of the 1/r^6 dispersion
terms. Just make the height of your cell somewhat lower. It really
should not matter much, whether you have 500 or 1000 Angstrom between
your graphene layers.

  Best regards,

  Bálint

-- 
Dr. Bálint Aradi
Bremen Center for Computational Materials Science, University of Bremen
http://www.bccms.uni-bremen.de/cms/people/b_aradi/


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