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Andrei V Scherbinin
andrei.scherb@gmail.com

if such potentials are available in a standard FF format (e.g., that for ECP or EFP),
or they can be designed (or simply re-written) in either of the two formats, you may
declare your potentials as ECP or EFP, respectively.

For example, in cluster models for ionic crystals, it is a common practice to use
conventional large-core ECPs (without explicit electronic shells) to represent cations
in the boundary region of the cluster.

Another issue is, how reliable cluster models are expected to be in describing bulk metals?

May be, there are some specific properties of more localized nature that can be explored
this way. But in general, cluster model seems not to reproduce the most specific (band-like)
electronic structure of metals due to cancelation of wave functions outside the cluster region,
except for, perhaps, clusters of very big size. In such a case, a better solution would be to
switch to periodic (band structure) models and software, where the size of a simulation cell
is much less than the expected size of a representative cluster model.

Regards, A.Scherb.



On Thu Aug 4 '11 2:17am, Amir Nasser Shamkhali wrote
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>Dear All
>I want to use one electron or capping potentials for some transition metal clusters. Using these potentials leads to edge atoms feel an emvironment similar to the bulk metal. How these potentials can be used in firefly?

>Sincerely