I am not familiar with such calculations. In general magnetocrystalline anisotropy is an effect due to spin-orbit coupling. Since this is a relativistic effect it mostly plays a role within the inner parts of the MT spheres of the atoms. What you could do is to identify which atoms are in which layers and switch on or off the inclusion of SOC in the treatment of these atoms. As described at https://www.flapw.de/MaX-5.1/documentati...n-2nd-variation you could use the socscale parameter for such a calculation. If you compare the MAE with and without SOC at certain atoms this may give you the quantities you are interested in. But this is just a guess: As mentioned I am not familiar with layer-resolved MAEs and I don't know whether the approach I sketch actually gives you what you want to see. This is something you have to think about in detail. I am not aware of any other mechanism to calculate a layer-resolved MAE with Fleur.

Dear Adriano,

I am not 100% sure I get the point, but in the workflow the outlined here, the SOC effects are calculated from changes in the eigenvalue sum. The changes in eigenvalues can of course not simply be decomposed in contributions from individual atoms. What you can do, would be to "switch off" SOC for some atoms by e.g. using the "socscale" parameter and then investigate the changes you get. If you do that for many atoms/layers it of course can become a bit of work and these "contributions" you will get there will not simply add up to the full result.
To get such a decomposition of the full SOC effect into additive terms for each atom, I think you would have to do e.g. 1st order perturbation theory in the SOC. Then the changes of the eigenvalues will be due to the expectation values of the changes of the SOC contribution to the Hamiltonian which can be decomposed into individual additive terms. We do this only for the "DMI" force theorem mode which does SOC on top of spin-spiral calculations using perturbation theory.

Hope this is of some help,

Daniel

Another remark:

The magnetic force theorem is an approximative technique. Of course, it is more precise to calculate the MAE on the basis of the total energies from self-consistent solutions for the different configurations of the SQA. But I guess you are aware of this.

I understand the figure caption such that this is an approach with the socscale parameter, though not in the sense that SOC is switched off in specific layers, but in the sense that it is only switched on in the the respective layer.

Yes, you have to find out by yourself which atom types ("atomGroup" in the inp.xml file) belong to each layer. The atomGroups in the inp.xml file have the same order as the numeration of the atom types suggests. So you can just have a look at the atom positions of each atomGroup and then count. Atom types are not the same as atom species.