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pekkosk / hotbit

ASE density-functional tight-binding calculator
GNU General Public License v2.0
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Homonuclear parametrization #17

Closed sarah-allec closed 6 years ago

sarah-allec commented 6 years ago

Hello,

I am trying to learn how to parametrize DFTB with hotbit. I am able to construct the CH and HC Slater Koster tables but I am having trouble doing the homonuclear cases (e.g., HH and CC). I noticed in the AuAu example that dimer, "bulk", and homogeneous clusters are used. I constructed a dimer and bulk trajectory for hydrogen by just copying the gold examples (and adjusting the bond lengths in the dimer). However, I am wondering if this is sufficient for the homogeneous cluster (i.e., replacing Au with H in the Au12-.xyz file and decreasing the bond lengths between the atoms). Any help is appreciated.

-Sarah

pekkosk commented 6 years ago

Using the geometry of the homogeneous cluster Au12- for other elements is a bad idea, as the geometry is specific for gold. For H dimer may be enough (since H clusters don't quite occur in nature) and for CC one could use graphene, diamond, nanotubes, fullerenes, and a selection of symmetric hydrocarbons.

sarah-allec commented 6 years ago

Makes sense. Thank you!