[CP2K-user] [CP2K:10218] Spin polarised calculation for bulk iron (16 atoms)

[Daniele Ongari]

Hi Tiziano, 
I'm interested in this topic because I have problem to make materials 
(MOFs) with Fe converge and I want to start to the bulk Fe as a test case.

I wonder how your suggestion is supposed to work (I'm using CP2K-5.1 too).
1) Without specifying the system MULTIPLICITY this is by default 0 (which 
is treated as 1 in CP2K) that means that no broken symmetry is occurring: 
spin1 and spin2 will be rescaled and basically the effect of specifying the 
MAGNETIZATION is null
2) If considering that the system has 16 Fe atoms, one used 1+16*2.3= 37.8 
as MULTIPLICITY (assuming ferromagnetic configuration), CP2K aborts with 
the error "An integer type object was expected".

So, how can someone specify a MAGNETIZATION that doesn't sum up into an 
integer total magnetization?

The problem I see is another, that I'm not able to make the calculation 
converge with MAGNETIZATION 2 and MULTIPICITY 1+16*2=33 (so no problems 
with non-integer numbers), but this is a problem to solve in the &MIXING 
section, right?
Do you have any working settings for make the bulk Fe converge? I think you 
managed to do so for the Delta-test of Stefaan Cottenier.

Thank you very much for your help

Daniele


Il giorno giovedì 26 aprile 2018 17:35:33 UTC+2, Tiziano Müller ha scritto:
>
> Hi Unmesh 
>
> Am 25.04.2018 um 12:18 schrieb Unmesh Mondal: 
> > I am new to cp2k and wish to do a spin polarised calculation of bulk 
> > Iron  (Fe : 16 atoms, gamma point). Switching on UKS (spin unrestricted 
> > Kohn Sham) ensures the spin polarised part  and the MULTIPLICITY " " 
> > ensures the initial spin state of the whole system. 
>
> Are you sure? Check your output right below "Guess for atomic kind: Fe". 
> This should tell you the used initial spin state. 
>
> With CP2K 5.1 and later you can use the MAGNETIZATION keyword for the 
> KIND section (with a value of 2.3 for iron) to get a proper initial 
> state, see 
>
> https://manual.cp2k.org/trunk/CP2K_INPUT/FORCE_EVAL/SUBSYS/KIND.html 
>
> If you are using an older version (<5.1) use the Broken Symmetry section 
> instead to achieve the same thing: 
>
>
> https://manual.cp2k.org/cp2k-4_1-branch/CP2K_INPUT/FORCE_EVAL/SUBSYS/KIND/BS.html 
>
> Best regards, 
> Tiziano 
>
> -- 
> Tiziano Müller 
> University of Zurich 
> Department of Chemistry 
> Winterthurerstrasse 190 
> CH-8057 Zürich 
>
> Tel: +41 44 63 54234 
> www.chem.uzh.ch 
> tiz... at chem.uzh.ch 
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20190828/c4885cf4/attachment.htm>