[Wien] Magnetic properties or 5d metals

[Pablo de la Mora]

El 03/06/11 08:06, Peter Blaha escribió:
> If it gives a small U for a 5d system, it gives the expected result.
>
> The method is reliable if   a)  most of the considered electrons (5d) 
> are localized
> within the atomic sphere and b) is only reliable when "LDA+U is 
> appicable, that means
> if "atomic physics" dominates and states are localized similar as in 
> an atom.
>
> Spin-orbit ??

Thank you, the Madsen and Novak method gives for Ir a value of Uh=0.7, 
but people use Uh=2.

For a metallic system the method seems to require a larger Uh, as you 
mention, the states are not localized.
Yes, SO is includded.

> Am 02.06.2011 14:13, schrieb Pablo de la Mora:
>> Dear WIEN users,
>> Compounds with 5d metals have magnetic properties, but due to the 
>> extended nature of the 5d orbitals the calculations give non-magnetic 
>> results, includding the Hubbard U (Uh).
>> I have calculated the Uh using the method proposed by G. Madsen and 
>> P. Novak:
>> Notes about constraint LDA calculations to determine U 
>> <http://www.wien2k.at/reg_user/textbooks/Constraint_U.pdf>
>> which gives me a small Uh.
>> To stabilize the magnetic state I need to use an unphysically large 
>> Uh. Any suggestions?
>>
>> Is this method suggested by Madsen and Novak accurate?
>> I have used in other compounds and it seems to give reasonable 
>> results, but these notes are not very clear (I could expand some 
>> issues in the notes to make them clearer).
>>
>>
>>
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>