[QE-users] Constrained_magnetization ='atomic' and starting_magnetization conflict in QE 7.2

[Alpin Novianus Tatan]

Dear all,

I am using constrained_magnetization = 'atomic' and starting_magnetization
in QE 7.2.
I notice that the value of the selected constrained moment is read from the
starting_magnetization tag. However, the two tags follow different
conventions.

For example, if I set:

starting_magnetization(2) = 3.2500000,
angle1(2) = 90.000000,
angle2(2) = 0.000000,

this is read as:


==============================================================================

     atom number    5 relative position :    0.2420   0.7171   0.3965

     charge :    13.248234  (integrated on a sphere of radius 0.185)

     magnetization :         41.831769    0.000006    0.000000

     magnetization/charge:    3.157536    0.000000    0.000000

     polar coord.: r, theta, phi [deg] :    41.831769   90.000000
0.000008

     constrained moment :     3.250000    0.000000    0.000000



==============================================================================


The constrained_magnetizaton tag reads 3.25 as the desired magnetic moment.

However, the starting_magnetization tag treats 3.25 as site magnetization
per valence electron, hence the massive 41.8 starting magnetic moment.

This slows convergence for sure, but I also suspect it could create other
problems such as magnetizing the neighboring atoms.


If I start with starting_magnetization = 0.25, which would give the correct
starting moment = 3.25, then the constrained moment becomes incorrect (only
0.25).

The printed constraint energy also becomes huge (100 Ry), due to the
incorrect constraint.


Is there a fix for aligning the convention in both tags? (so that I both
start and constraint with 3.25 moment)


There seems to be a change made for constrained_magnetization in QE 7.4 but
I'm unsure if it's related to this issue.

Due to other problems in the version 7.4, I wish to stick to QE 7.2 and
modify only parts related to this issue if possible.



Thank you.

Best regards,


Alpin N. Tatan

Department of Physics,

The University of Tokyo.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20251129/2c488275/attachment.html>