[DFTB-Plus-User] Error with SiO2 high pressure simulations

[Bálint Aradi]

Dear Nir,

> I am trying to use the pbc-0-3 parameter set to compute the shock Hugoniot of alpha-quartz.  When I set the max angular momentum for Si to “d” (as suggested in the Si-O.skf file), at somewhere between 40-50% compression I get an error message stating: “Failure in diagonalisation routine dsygv, non-positive definite overlap! Minor   1011 responsible.”  This issue is removed if I set the max angular momentum on Si to “p”.  Is there any kind of patching I can do in order to allow for stronger compressions while using d electrons for Si?


 The problem is, that your basis set will become linearly dependent,
making the diagonalization of the Hamiltonian impossible. There is not
really much you can do to prevent this.

    Best regards,

  Bálint

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


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