[Pw_forum] A question on atomic magnetic moments

[Giovani Faccin]

Dear QE users,

My first post on this list! Given the daily flow of messages, I'm glad to
see that this is an active community!

I'm trying to setup a simulation of a system containing iron. In order to do
it, first I'm first testing the dimer and bulk, in order to see if they are
being calculated correctly.

I'm using the Fe.pbe-nd-rrkjus.UPF<http://www.quantum-espresso.org/pseudo/1.3/UPF/Fe.pbe-nd-rrkjus.UPF>
pseudo from the online database, with a 3d74s1 valence configuration and +1
magnetization.

I've obtained a dimer equilibrium bond length of 2.05 angstroms (experiment:
2.02) and a vibrational frequency of 330 cm^-1 (experiment: 300). I'm happy
with these results!

Using another DFT code (OpenMX), also with GGA, I've obtained 2.10 angstroms
for the equilibrium bond length and also 330 cm^-1 for the vibrational
frequency.

What puzzles me is the system magnetization. These are the results I'm
getting (in units of Bohr mag.):

Openmx - scalar relativistic: 6.62
Openmx - full relativistic, non collinear: 6.86
Quantum Espresso - : 7.14

Theoretical DFT literacy values: 6.00
Experiment: 6.5 +/- 1

My question: shouldn't those numbers be integers? If so, what could be
causing this?

Any information you need, just ask.

Thank you!


-- 
Giovani M. Faccin
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