[Pw_forum] GGA not converge

[Sakhrawi Taoufek]

Dear all 

i am calculating the lattice parameter for antiferromagnetic FeRh, it dosen't converge.
###############################&control
    prefix='FeRh_afm',
    pseudo_dir = '***/',
    outdir='***/'
 /
 &system
    ibrav= 0,    celldm(1) =$alat,
    nat=4,    ntyp=3,
    ecutwfc = 20,
    occupations='smearing',
    smearing='mv',
    degauss=0.02,
    nspin=2,
    starting_magnetization(1)= 0.3,
    starting_magnetization(2)= -0.3,
    starting_magnetization(3)=  0.0,
  /
  &electrons
mixing_mode = 'plain' ,
mixing_beta = 0.5,
diagonalization = 'david' ,
conv_thr = 1.0d-7,
electron_maxstep=1000,
 /
CELL_PARAMETERS {cubic}
   1.0000   0.0000   0.0000
   0.0000   1.0000   0.0000
   0.0000   0.0000   1.0000
ATOMIC_SPECIES
 Fe1 55.85    Fe.pbe-spn-rrkjus.UPF
 Fe2 55.85    Fe.pbe-spn-rrkjus.UPF
 Rh 102.91    Rh.pbe-spn-rrkjus.UPF
ATOMIC_POSITIONS {crystal}
   Fe1      0.00000000  0.00000000  0.00000000
   Fe2      0.50000000  0.50000000  0.50000000
   Rh       0.25000000  0.25000000  0.25000000
   Rh       0.75000000  0.75000000  0.75000000
K_POINTS {automatic}
   10 10 10 1 1 1

###############################
see the attached file please.
any suggestion will be appraciated.
--------------------------------

Sakhraoui Taoufik
Ph.D student 
Faculty of Sciences of Monastir
Department of Physics
L.M.C.N
Monastir, Tunisia
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