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[Ganesh Panchapakesan <gpanchap@gmail.com>]

Dear Bernard,

Thank you for the reply.  Indeed, I see that using imag. Ylm's, DOS(L,M)==DOS(L,-M).

It is also clear that if I knew the projected 'dos' in terms of the real. sph. harms., then DOS(L,M)=(dos(L,M)+dos(L,-M))/2.0 , where 'dos' is for projections on real sph. harms.  But going the other way around, from DOS to dos, doesn't seem to be possible due to the identity in the first line.  It seems I have to explicitly compute 'dos' .  Maybe there is a relation between dos(L,M) and dos(L,-M) that I am missing, but I don't see it in my derivation.

Thanks.

Ganesh

On Wed, Jan 13, 2010 at 9:11 AM, Bernard Amadon <bernard.amadon@cea.fr> wrote:

Dear Ganesh

Prtdosm computes M-resolved partial dos in the complex spherical harmonics, it explains why you have
DOS(L,M) == DOS(L,-M) (without spin-orbit). In the contrary, LDA+U occupation matrix is in the real spherical harmonics basis.
You could use prtfatbands which computes band structure in the real spherical harmonics basis, but
to have the partial dos, you can use the conversion from complex to real spherical harmonics,
apply it to the dos, and you will have the partial dos in the real spherical harmonics which is more
convenient for the interpretation.

Best regards
Bernard





Ganesh Panchapakesan a écrit :

Dear All,

I am trying to compute the partial DOS (projected on to (atom,L,M) ) of an anti-ferro. system using PAW - GGA with v5.7.4.  The system is metallic.  I use the following options: prtdos 3, prtdosm 1, ngkpt 10 10 10, shiftk 0 0 0, natsph 1, iatsph 1, ratsph 2.31, iscf -3 to compute the DOS using the tetrahedron method and project onto the (L,M) centered on atom 'i' (ratsph =  r_c of PAW dataset)

Although the partials obey the condition: Sum(m)DOS(L,M) == DOS(L), the result of the partials always follows this identity: DOS(L,M) == DOS(L,-M), even when I expect the different d-orbitals (i.e. L=2) to have a different occupations (I see that from the occupation matrices in a +U calculation). As a result, the integral of the  DOS(L,M) up to the Fermi level does not correspond to the occupation number from the +U calculation.  I have tried with both the pure GGA density and GGA+U density as inputs to the DOS calculation.

Any suggestions/clarifications will be very much appreciated. If anyone knows that this is a problem but it is fixed in v5.8.4 that would also help.
Thanks.

Ganesh  

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