Tutorial ends with a question “Is it different from the one at the start of the initial run?”. I am wondering if there is any further information on this. Does aiida have a workchain to handle magnetic configurations converging to a state away from the initial configuration?
Thanks,
Kayahan
Dr. Kayahan Saritas
R&D Associate, Materials Theory Group
Materials Sciences and Technology Division
Oak Ridge National Laboratory
Could you elaborate a bit more on what you have in mind, e.g. the use-case of such a WorkChain?
“Is it different from the one at the start of the initial run?”
That statement is part of the Passing the magnetic configuration section. I’m not the one who wrote this part of the documentation, but I’m assuming that it just refers to checking that the calculated magnetic moments have indeed been passed to the new builder, instead of the default population, i.e. setting all d and f electrons to spin-up (and for all other elements a starting-magnetization of 0.1.
Does aiida have a workchain to handle magnetic configurations converging to a state away from the initial configuration?
If you are referring to initialising different AFM configurations, AiiDA-QE only supports to create the corresponding structure and magnetic moments, as highlighted in the documentation, given that you provide the desired configuration. For example, there is no function that takes care of generating all symmetrically unique arrangements of initial spins. This is something you’d need to take care of yourself.
Otherwise, if you are referring to pushing the system to a certain magnetic state, there is the total_magnetization keyword in pw.x, which allows you to specify and fix the total magnetization of your system pw.x: input description. In case you had in mind to use this keyword, you can of course do this via the normal AiiDA-QEWorkChains as well.
Thanks for the response. I think you are right, that question in the tutorial refers to passing the magnetic configuration from builder to the qe calculation.
I had assumed that the tutorial is referring to comparing converged and initial magnetic moments. My question is the following: For example, I could start the calculation with AFM configuration, but it could converge to a ferrimagnetic configuration (with different magnitude of moments), where both system could have a total magnetic moment of zero. I am asking about if there is a workchain in aiida-qe plugin that helps keeping a better control over matching the input and output magnetic configurations.
workchain in aiida-qe plugin that helps keeping a better control over matching the input and output magnetic configurations
Do you want to “push” the system to a certain configuration that should be kept, e.g. you initialize as an AFM and should also stay in an AFM configuration? To the best of my knowledge, this is not possible. Even in QE, the system might converge to a different configuration.
If you simply want to compare the initial and final magnetic configuration, you can access the converged magnetic moments via calc.outputs.output_trajectory.get_array('atomic_magnetic_moments')[-1].
Apart from that, there is no specific WorkChain in AiiDA-QE dedicated to magnetism.
If I didn’t understand your use-case correctly, feel free to clarify and to ping me again