I am confused the proper choice for magmom. Is it based solely on unpaired spins or is it the spin plus orbital angular momentum (sum of l+2s). That is, if I have one unpaired electron in an s orbital magmom = 1, but what is it for an unpaired electron in a p or d orbital?
Use of Magmom when l is not zero
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KWH
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martin.schlipf
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Re: Use of Magmom when l is not zero
MAGMOM is only the initial guess for the spin component. During an iteration the density will be updated to find the ground state. If you set LORBIT you can read the final spin magnetic moments. To compute the orbital moments you need to set LORBMOM as well (note that this requires spin-orbit coupling LSORBIT).
Furthermore keep in mind that the magnetic moments are only defined in a sphere around the atom so the sum of all magnetic moments is not equal to the magnetization because there may be some density in the interstitial region.
Martin Schlipf
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KWH
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Re: Use of Magmom when l is not zero
Thank you for the information. Is the total magnetic moment available in some form?
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martin.schlipf
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Re: Use of Magmom when l is not zero
What do you mean with total magnetic moment?
If you mean the total magnetization, that is logged to the output file in every iteration. This does not include the orbital magnetization.
If you mean the total magnetic moment per atom, this is the sum of spin and orbital moment both of which are logged to the output if you set LORBIT, LSORBIT and LORBMOM. You can use py4vasp to read the moments from the vaspout.h5 file.
Martin Schlipf
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