[QE-users] pw.x - choosing starting_magnetization value for specific expected total magnetization

[Paolo Giannozzi]

Actually this is going to change in the next release:
- if -1 < starting_magnetization < 1, it works as described below
- if |starting_magnetization| >= 1, it is the starting magnetization in 
Bohr magnetons

Paolo

On 22/02/2024 16:47, Guido Fratesi wrote:
> 
> Dear Abdul,
> 
> the starting magnetization is here defined as (N_UP-N_DW)/(N_UP+N_DW) so
> a value of 1 means fully polarized, N_UP=N and N_DW=0.
> 
> Eg if you want 3muB for an atom having 8 electrons you need to put a
> value of 3/8.
> 
> To obtain the various minima you may have to sample various initial
> configurations. It's not at all guaranteed that the calculation will
> keep within the basin that you want, and you may need to reduce the
> mixing beta, or possibly to constraint the magnetization during the SCF
> cycle, and possibly run a following calculation restarting with that
> density but without the constraint.
> 
> Are you using DFT+U? If not, adding a very small U (1e-5) and setting
> verbosity=high will not change the solution but allow you to track the
> occupation of the atomic orbitals in detail during the SCF loop.
> 
> HTH,
> Guido
> 
> 
> -- 
> Guido Fratesi
> 
> Associate Professor
> Physics Department "Aldo Pontremoli"
> University of Milan
> Via Celoria 16, 20133 Milan, Italy
> 
> Phone: +39 02 503 17348
> email: guido.fratesi at fisica.unimi.it
> web:   https://sites.google.com/site/guidofratesi/
> 
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-- 
Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
Univ. Udine, via delle Scienze 206, 33100 Udine Italy, +39-0432-558216