[Wien] open shell case [Si and Ge]

[Peter Blaha]

And you should use TEMP 0.002  instead of TETRA to get better scf 
convergence.

On 11/03/2017 06:52 AM, Stefaan Cottenier wrote:
> Following Hund’s rules, the atomic ground state for Si and Ge is
> spin-polarized (‘open shell’):
>
>
>
> https://www.webelements.com/silicon/atoms.html
>
>
>
> Hence, yes, you need -sp to find a meaningful value for the free atom
> total energy.
>
>
>
> Stefaan
>
>
>
>
>
> *Van:*Wien [mailto:wien-bounces at zeus.theochem.tuwien.ac.at] *Namens
> *Gavin Abo
> *Verzonden:* vrijdag 3 november 2017 5:42
> *Aan:* wien at zeus.theochem.tuwien.ac.at
> *Onderwerp:* Re: [Wien] open shell case [Si and Ge]
>
>
>
> Feel free to correct me if I'm wrong, but I think Si and Ge have an even
> number of electrons (or paired electrons).
>
> For Si, 4 electrons in the 3s^2 3p^2.  For Ge, 4 electrons in the 4s^2
> 4p^2. [1]
>
> This making them closed shell [2].
>
> In Prof. Blaha's example for free atoms [3], spin-polarized (runsp_lapw)
> is used for open shell (or non-closed shell [4]) Li (1 electron in 2s^1)
> and B (3 electron in 2s^2 2p^1) and non-spin polarized is used for
> closed shell Be (2 electron in 2s^2).
>
> I don't know why it is fluctuating, diverging?  Is the box you used
> containing the free atom large enough?  I remember that 12x12x12
> angstrom usually might be large enough [5].
>
> [1]
> https://en.wikipedia.org/wiki/Electron_configurations_of_the_elements_(data_page)
> [2]
> https://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/msg11320.html
> [3]
> https://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/msg16691.html
> [4] http://susi.theochem.tuwien.ac.at/reg_user/faq/cohesive.html
> [5]
> https://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/msg12815.html
>
> On 11/2/2017 7:06 PM, chin Sabsu wrote:
>
>     Dear Peter Sir,
>
>
>
>     Do Si [S^23P^4]  and Ge [4S^24P^2] are also an open shell case?
>
>
>
>     Because my Si atomization energy is fluctuating without -sp switch
>     after 55 scf cycles also.
>
>
>
>
>
>
>
>     Sincerely
>
>
>
>     Chin
>
>
>
> _______________________________________________
> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> SEARCH the MAILING-LIST at:  http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
>

-- 

                                       P.Blaha
--------------------------------------------------------------------------
Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
Phone: +43-1-58801-165300             FAX: +43-1-58801-165982
Email: blaha at theochem.tuwien.ac.at    WIEN2k: http://www.wien2k.at
WWW:   http://www.imc.tuwien.ac.at/TC_Blaha
--------------------------------------------------------------------------