[Wien] Qestion about DOS results

[Fecher, Gerhard]

please read
Y. Yun et al; Phys Rev B 83 , 075109 (2011)
the authors found a ferromagnetic state for alpha U3O8 with moment at only one of the U atoms,
however, they also remarked that experiments resultes always in a paramagnetic state.

However this was for a particular structure of U3O8, and there is not only one but several, you don't ever tell which one you use ?
In Yun's paper the b lattice parameter (7.2 AA) is overestimated by 10% compared to the experiment (6.7 AA),

My experience tells: if one uses LDA+U, one can make everything ferromagnetic, even Alkali metals
therefore you should take the comment of Laurence Marks very serious ("Also, I suggest some care with +U for f's. At least for the 4f +U over-localizes them.")

PS.: you might need to create a suitable cell to check for antiferromagnetic order, as you have actually only 3 U atoms in the cell
otherwise you may end up with some ferrimagnet (again i instead of o)

Ciao
Gerhard

DEEP THOUGHT in D. Adams; Hitchhikers Guide to the Galaxy:
"I think the problem, to be quite honest with you,
is that you have never actually known what the question is."

====================================
Dr. Gerhard H. Fecher
Institut of Inorganic and Analytical Chemistry
Johannes Gutenberg - University
55099 Mainz
and
Max Planck Institute for Chemical Physics of Solids
01187 Dresden
________________________________________
Von: Wien [wien-bounces at zeus.theochem.tuwien.ac.at] im Auftrag von shaymlal dayananda [kcsdayananda at yahoo.com]
Gesendet: Dienstag, 11. Dezember 2018 23:06
An: A. Mailing List for WIEN2k Users
Betreff: [Wien] Qestion about DOS results

Dear all


Sorry, my reply to the original mail chain is waiting for the moderator approval! So I am sending this as a new email.

............................................................
I have actually considered hubard-U (4.5 eV is included) and spin orbital coupling also added. My structure is U3O8,

case.indmc
 -12.0000         Emin cutoff energy
  2               number of atoms for which density matrix is calculated
  1  1  3         index of 1st atom, number of L, L1
  2  1  3         index of 1st atom, number of L, L1
  0  0            krad, kls


case.inorb
  1  2  0                     nmod, natorb, ipr
 PRATT  1.0                    BROYD/PRATT, mixing
  1 1 3                          iatom nlorb, lorb
  2 1 3                          iatom nlorb, lorb
  1                              nsic 0..AMF, 1..SIC, 2..HFM
   0.3307 0.00        U J (Ry)   Note: we recommend to use U_eff = U-J and J=0
   0.3307 0.00        U J



I am having a followup question for your comments.
1. Can I conclude FM for my system?
  because: atom-1(uranium1) is non-magnetic, atom-2 uranium (multiplicity is 2 for this atom) has a magnetic moment  of 0.71935. These two  uranium has parallel magnetism.

2. This system is U3O8, (not U2O5). It has only 11 atoms in the unit cell as 1 (U), 2(U), 2(U), 3(O), 4(O), 4(O), 5 (O), 6(O), 6(O), 7(O), 7(O).
With this, is this possible to accept the obtained DOS?
(And do we necessarily should get different DOS for FM/AFM cases for their spin UP/DN cases?

Thank you

Shayam