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[<ldamewood@gmail.com>]

I've been calculating the gap and magnetization in ZB CrAs using abinit. As a
reference, I've been comparing my calculations to Phys. Rev. B 67, 224420
(2003). When I preform an LDA calculation, I get good agreement with the
lattice parameter and magnetization. For the GGA calculation, I get a much
larger lattice parameter and a non-integer magnetization (an integer
magnetization would be expected for half metallic CrAs). Specifically, acell
should be 10.69 whereas GGA gives me 11.2. magnetization should be exactly 3
while GGA gives 2.95.

I've included an input below. Can anyone tell me if I am doing something
incorrectly? I'm not doing anything vastly different in my GGA calculation 
than
in my LDA calculation so my guess is that the pseudopotential is not well
suited for this calculation. I'm new at this so any help is appreciated.

-Liam

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For LDA, I used the FHI pseudopotentials and for GGA, I used PBE from the FHI
code. Here is my input file for a GGA calculation for the acell convergence.

[damewood@**** CrAs_1]$ cat CrAs_1.in
ndtset    15
acell:    10.0 10.0 10.0
acell+    00.1 00.1 00.1
rprim     0.0  0.5  0.5
          0.5  0.0  0.5
          0.5  0.5  0.0
ntypat    2
znucl     24 33
natom     2
typat     1 2
xred      0.00 0.00 0.00
          0.25 0.25 0.25
nsppol    2
spinat    0.00 0.00 6.00
          0.00 0.00 -3.00
nband     12

ecut      30.0

kptopt    1
ngkpt     27 27 27
nshiftk   4
shiftk    0.5 0.5 0.5
          0.5 0.0 0.0
          0.0 0.5 0.0
          0.0 0.0 0.5

occopt    4
nstep     20
toldfe    1.0d-6
tsmear    0.01
prtdos    2