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I have a magnetic crystal system. I want to calculate the total energy of the system if the magnetization direction is aligned in different directions such as [110], [010]. By default Quantum ESPRESSO measures the magnetization along [001] direction and I am not getting any parameter to change the direction in the input file. Actually, I want to produce the band structures for different magnetic directions.

Is it possible to change the direction of magnetization in Quantum ESPRESSO? How can I do that?

Thank you!

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  • $\begingroup$ I'm not super familiar with this area, but would this be what you are looking for: quantum-espresso.org/Doc/pw_user_guide/…? Quantum Espresso allows you to do a noncollinear spin calculation, which seems like it would allow you to change the magnetization direction (if I'm understanding the question correctly). $\endgroup$
    – Tyberius
    Commented Dec 2, 2021 at 17:05
  • $\begingroup$ @Tyberius, Thank you for your response. Yes, it allows the noncollinear spin calculation. We can also allow magnetization direction to change for a particular atom/ion. But I think during the calculation it will eventually change the direction of each atom/ion randomly in order to achieve minima, isn't it? $\endgroup$
    – UJM
    Commented Dec 2, 2021 at 18:22
  • $\begingroup$ @Tyberius I'm not sure if you saw UJM's qustion, so I'm just reminding you of it in any case. $\endgroup$ Commented Jan 14, 2022 at 1:54
  • $\begingroup$ @UJM I don't know much about Quantum Espresso, but I expect you are right that that the spin directions will change during an optimization. There might be a way to fix it throughout the calculation, but I'm not sure. $\endgroup$
    – Tyberius
    Commented Jan 14, 2022 at 2:26

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This should be possible. You should impose noncollin = .true., then constrained_magnetization = 'atomic direction'. Finally with angle1 and angle2, you can set the precise direction.

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  • $\begingroup$ But isn't the magnetization direction will change throughout the scf calculation? I think we are just giving the initial guess of magnetic directions by setting the angles? Please correct me if I am wrong. $\endgroup$
    – UJM
    Commented Sep 23, 2022 at 17:39
  • $\begingroup$ You are right, but the change will be "constrained". That's why you have the variable lambda which controls how constrained you want the solution, i.e., how different to the initial magnetization are the solutions you want to admit. $\endgroup$ Commented Sep 24, 2022 at 16:32

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