SOC calculation in VASP

Question on input files/tags, interpreting output, etc.

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SOC calculation in VASP

#1 Post by alok_shukla1 » Mon Aug 08, 2022 4:14 pm

Dear All,

I have some queries regarding spin-orbit coupling (SOC) calculation.
Applying SOC for any system, tags related to SOC should be included in relaxation or in the SCF cycle. Here my concern is, one should apply the SOC tag in the beginning, i.e., during the relaxation process or after relaxation in the SCF cycle one should apply.
If it is in the SCF cycle, then for the calculation of formation energy, one should consider the ground state energy of the system from relaxation output or from SCF (SOC included) output.
One more thing, if the system has some magnetic moment, then using SOC, whatever is getting, one should report that magnetic moment or without SOC.


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Re: SOC calculation in VASP

#2 Post by alexey.tal » Tue Aug 09, 2022 3:50 pm


For light elements SOC has a relatively small effect on the electronic structure of solids and is therefore neglected in the structure optimization. Nevertheless, it is always worth checking for a specific case.

I am not sure what you mean by your last question, but if you observe that the magnetic moment with SOC differs, it means that by neglecting SOC you omit some potentially important physical effects.

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