[Q-e-developers] ALL electron and PSEUDOPOTENTIAL data base

[Layla Martin-Samos]

Grazie mille Nicola is exactly the kind of information that we need! soon I
will send the doodle pool for a skype meeting.

best regards

Layla

Le 8 février 2012 15:58, Nicola Marzari <nicola.marzari at epfl.ch> a écrit :

>
>
>
> Dear All,
>
> here is my summary of what is needed for the specific case of
> d- and f-elements - I personally think it's the most urgent, since
> the other elements tend to be easier to pseudize, and we have
> a reliable set for them in the ps_library of Andrea.
>
> For d- and f-elements, the general gist is that for each element
> we want to have a set of standard structures that span all relevant
> oxidation states (e.g. bcc metal, antifluorite, rocksalt,  zirconia,
> and "ReO3" (i.e. XO3)), and, for a given spin-polarized exchange
> correlation functional (starting from LSDA) we want to store,
> with the appropriate units specified, the
>
> 1) equilibrium lattice parameter
> 2) bulk modulus, and eventually elastic constants
> 3) optical phonons at the gamma point (i.e. all phonons at gamma
> that are not zero)
> 4) electronic bandstructure (spin up and down) along pre-defined paths
> in the BZ (attached - paths to be stored also in the database)
> 5) total and absolute magnetization
>
> Ideally there should be ways to take the all-electron
> data, and the pseudo data, and calculate a figure of merit
> on the agreement between the two (or between different all-electron
> calculations), defined according to mean sqaure displacements between
> AE and PS results for 1) to 5), with weights we'll need to figure out.
>
> I attach here a first set of definitions for these standards,
> prepared by Cheol Hwan Park (a postdoc of mine, at MIT - he will
> move to a faculty position at Seoul National U. in September).
>
> Cheol Hwan and I would be delighted to interact on the framing of the
> database structure. Equally or even more urgent for us is *having* some
> all electron calculations to compare with, so that we can start optimizing
> the pseudos. We need La and Eu, in the rocksalt (LaO and
> EuO) structure, and ideally also in the zirconia (so it's 4 calculations
> that we are asking for). Attached are the computational set up that we
> have used, the k-points used for band structure calculation, examples of
> pwscf input files for convenience, and an example result file (EuO
> rock salt structure).
>
> The following are part of the key information in the attached file -
> typically for a pseudo calculation we would need to specify these
> computational parameters - we just need to discuss if for the AE
> calculations Gaussian smearing is the best choice, or Fermi-Dirac
> would be more commonly used.
>
>                        nicola
>
>
> # Computational setup
> #
> # spin-polarized (nspin=2)
> # PZ LDA exchange-correlation
> # scalar relativistic
> #
> # wavefunction cutoff: 80 Ry
> # charge density cutoff: 320 Ry
> # Troullier Martins norm-conserving pseudopotential
> # 12 x 12 x 12 grid with shift (1/2, 1/2, 1/2)
> # Gaussian smearing by 0.02 Ry
> #
>
> ------------------------------**------------------------------**----------
> Prof Nicola Marzari, Chair of Theory and Simulation of Materials, EPFL
>
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