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I have seen specific ways of constructing input files for

How can I represent a paramagnetic material in plane wave DFT codes like Quantum ESPRESSO. Do we assign opposite moments with different magnitudes? Or we do we assume the material to be Non-magnetic?

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Paramagnetic materials have fluctuating magnetic moments that cannot be described using density functional theory. They can be properly described using, for example, dynamical mean-field theory.

Having said this, a typical approach to model paramagnetism in DFT is to build a large supercell of the material and to place randomly oriented magnetic moments on each atom. I have never explored these calculations in detail, so others may be able to comment on the merits of this approximation.

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  • $\begingroup$ Thank you, So is it safe to do a non spin polarized calculation in order to study electronic properties ? $\endgroup$
    – Atom
    Jan 20, 2021 at 4:58
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    $\begingroup$ @Atom is it a DFT calculation? Kohn-Sham DFT practically assumes absolute zero temperature, so spin-polarized calculations only make sense for magnets (FM, AFM etc) $\endgroup$
    – Xivi76
    Jan 20, 2021 at 6:33
  • $\begingroup$ @Xivi76 That makes sense! Thank you! I'm pretty new to DFT and solid state physics, thats why $\endgroup$
    – Atom
    Jan 20, 2021 at 7:37
  • $\begingroup$ @ATOM it is not true to replace paramagnetic with non magnetic, for example in case of FCC iron, lattice parameter of non-magnetic iron is 3.45 while experimental results is far off $\endgroup$ Mar 15, 2021 at 19:46
  • $\begingroup$ @pranavkumar So how should I proceed?/ $\endgroup$
    – Atom
    Mar 16, 2021 at 8:33

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