[Pw_forum] unit cell of Beta-GaSe crystal

[Ayça Kırağası]

Dear All Pw-users !

I'm a new pw user.
I want to calculate total energy of B-GaSe  crystal (hexagonal structure).
Altough I tried so hard, I couldn't set up unit cell of B-GaSe in Pwscf.
I couldn t see correct atomic structure of GaSe. I don t know where ı am
wrong.
Can anybody help me ! please !
I used parameters in the attached files. Also, my input file follow as

(lattice parameters a=3.73A  , c=15.919A,  z1=0.1003 and z2=0.1701


control
    calculation='scf'
    restart_mode='from_scratch',
    tstress = .true.
    tprnfor = .true.
    prefix='810-28',
    pseudo_dir = '/home/projet/pseudo/',
    outdir='/home/projet/tp/'
 /
 &system
    ibrav=0,
    celldm(1)=7.051,
    nat=8,
    ntyp=2,
    ecutwfc =50.0,
    ecutrho = 600.0,
 /
 &electrons
    diagonalization='david'
    conv_thr = 1.0e-6
    mixing_beta = 0.7
 /
ATOMIC_SPECIES
 Se  1.0 Se_pz.upf
 Ga  1.0 Ga_pz.upf
ATOMIC_POSITIONS {alat}
Se -0.5     0.28867  0.1003
Ga  0.0     0.0      0.1701
Ga  0.0     0.0      0.3299
Se -0.5     0.28867  0.3997
Se  0.0     0.0      0.6003
Ga -0.5     0.28867  0.6701
Ga -0.5     0.28867  0.8299
Se  0.0     0.0      0.8997
K_POINTS {automatic}
6 6 6 0 0 0

CELL_PARAMETERS {hexagonal}
 1.0   0.0   0.0
 0.5   0.866 0.0
 0.0   0.0   4.26
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