relaxation using quantum espresso

[sabrineayari]

Hello
i am new in dft calculation.now i am using quantum espresso
i wanted to do a calculation of the relaxation of the structure , but when i write in the
cell_dofree='ibrav' an error msg appears
however if i change it by cell_dofree='all' it works.

can you help me to understand why it doesn't work with cell_dofree='ibrav'

Thanks .

this is the program

&CONTROL
  calculation = 'vc-relax'
  outdir = './out/'
  prefix = 'aiida'
  pseudo_dir = './pseudo/'
  forc_conv_thr = 1e-4
/
&SYSTEM
  ibrav = 4
  a= 3.76102458e+00
  c=6.11797100e+00
  nat = 3
  ntyp = 2
  ecutwfc =   5.0000000000d+01
  occupations = 'smearing'
  smearing = 'gauss'
  degauss =   1.00000e-02
/
&ELECTRONS
  conv_thr =  1.00000e-06
/

&ions
ion_dynamics='bfgs'
/

&cell
    cell_dofree='ibrav'
    cell_dynamics='bfgs'
    press=0.0
    press_conv_thr=0.5
   
/

ATOMIC_SPECIES
Pt 195.084 pt_pbe_v1.4.uspp.F.UPF
Se 78.96 Se_pbe_v1.uspp.F.UPF
ATOMIC_POSITIONS {crystal}
Pt 0.0000000000 0.0000000000 0.0000000000
Se 0.3333333333 0.6666666667 0.2135830000
Se 0.6666666667 0.3333333333 0.7864170000
K_POINTS {automatic}
6 6 2 0 0 0