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[Matthieu Verstraete <mjv500@york.ac.uk>]

> I am expecting that the value of the integrated DOS difference between up and 
> down spins on Cr1 should be almost zero for l=0,1,3,4 and equal to the moment 
> M for l=2.  At Cr2, I should get similar answer except that for the d shell 
> the difference is -M (since the structure is AF). I expect M ~ 1.5 Bohr. 
> Magneton.
Ah! Now the value output is summed over m: it only depends on l. Someone 
working with David Vanderbilt's group has been thinking of generalizing 
the code, but I don't know if there is any progress yet.

> If I choose ratsph=2.1 a.u. on the Cr sites, what I get for the integrated 
> LDOS is the following:
>
> l =                         0         1          2         3        4 
> Cr1: spin up               0.09      3.05       2.54      0.03     0.01
>    spin down               0.01      0.10       0.03      0.00     0.00
> Cr2: spin-up               0.09       3.05      0.89      0.03     0.01
>    spin-down               0.01       0.10      0.07      0.00     0.00
This is indeed strange: the two Cr should be equivalent through some (AFM) 
symmetry operation, and the other channels are identical, but only for the 
spin up, instead of swapping spin up/down.

Could you try to output all the atomic LDOS, to see if the atoms are being 
selected wrong? And if any other atoms are incorrectly inequivalent?

> If I compute the moment on Cr1 and Cr2 by integrating the density within a 
> cube...
which density are you integrating? The spin up/down in the full unit cell?

> Thank you very much again.  (please look at the input file variables as 
> pasted below).  Note I am not using nsppol=1, nspden=2 here. Do you think 
> that might be part of the problem? I would expect that it only speeds up the 
> calculation and the final result wouldn't change.
Should be correct. Using nsppol=1 would definitely give the same result 
for up/down, as the wavefunctions are the same, and no reference to the 
density is made in the projection on Ylm. In your case the d channel is 
different, so it's not that.


Matthieu

--
================================================================
Dr. Matthieu Verstraete                 mailto:mjv500@york.ac.uk
Dept. of Physics, University of York,     tel: +44 1904 43 22 08
Heslington, YO10 5DD York, United Kingdom fax: +44 1904 43 22 14