[Pw_forum] NiMnSb calculations

[ramesh kumar]

Dear all and  Dr. Alberto Debernardi

i am learning band structure for half metallic ferromagnets. To start with i am trying to do for NiMnSb (debernardi etal Volume 23, Issues 6-8, 15 December 2003, Pages 743-746). i used the same pseudo potential and k_points grid but i am not able to reproduce the band structure.

the problems i faced

1. fluctuations in the convergence (despite 20%  increase of the # of bands)
2. all the bands are concentrated within 5 ev which is different from the Dr. Alberto paper.

3. i got half-metallic gap of ~ 1.2 ev 

i dont know whether i am going in the right direction. 

Here with i am giving the input file plz correct me if i had committed blunders in the input file.
 &control
    calculation='scf'
    restart_mode='from_scratch',
    pseudo_dir = '/usr/local/espresso-3.2.3/pseudo/',
    outdir='/home/mmm-lab/tmp/'
    prefix='nimnsb-example'
    
 /
 &system
    ibrav=2, celldm(1) =10.77, nat=3, ntyp=3,
    nspin = 2, ecutwfc = 35.0, ecutrho = 560.0, nelec=22, tot_magnetization=4,
    occupations='smearing', smearing='methfessel-paxton', degauss=0.02
 /
 &electrons
    diagonalization='david'
    conv_thr = 1.0e-6
    mixing_beta = 0.7 
 /
ATOMIC_SPECIES
 Ni 58.69  Ni_ps.uspp.UPF
 Mn 54.93  Mn_KB_LDA.uspp.UPF 
 Sb 121.76 Sb.pz-bhs.UPF

ATOMIC_POSITIONS
 Mn 0.25 0.25 0.25
 Ni 0.0 0.0 0.0
 Sb 0.75 0.75 0.75
K_POINTS {automatic}
8 8 1 0 0 0 



With regards

K. Ramesh Kumar
Research Scholar
Department of Physics
IIT-Madras
Chennai-600 036
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