[DFTB-Plus-User] about cutoff in SK file

[Goldman, Nir]

Hi,

Take a look at the first line in the .skf file of interest.  The first number corresponds to the distance in atomic units (au) between grid points. The second number (integer) corresponds to the number of grid points computed in the file. For example, in the C-C.skf file in the mio-0-1 set, the distance between grid points is 0.02, and the number of grid points is 500, so the cutoff for the Hamiltonian interactions is 10 au. Keep in mind, the cutoff for the repulsion energy is likely much smaller than that, in general.

Hope that helps,

Nir

--
Nir Goldman
Chemical Sciences Division, PLS
Lawrence Livermore National Laboratory
P.O. Box 808, L-288
Livermore, CA 94551-0808
Phone: (925) 422-3994
Fax: (925) 422-2382
https://www-pls.llnl.gov/?url=about_pls-scientific_staff-goldman_n

On 9/8/12 2:38 AM, "gxaaas" <gxaaas at gmail.com<mailto:gxaaas at gmail.com>> wrote:

Hi all,
   Could some tell me something on the cutoff for the adjacent two atoms in the SK file ?  If the distance between two atoms (like CC) is 4 angstrom, is there some interaction between them in dftb calculation?  Thanks !

________________________________
gxaaas
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