[QE-users] alat Units in VC-relax query

[Sri Matta]

Hi all

Recently started using QE.
I have query on 'alat' units from input file to output in 'vc-relax'.

Input alat= 8.04590 and the vc-relaxed file the alat is about 15.
Both input and out put are copied below.

I know the vc-relax will do full relaxation of cell parameters. But changing the value to almost 'double'? I have a doubt, if it is converting some units in out put?
Can anyone help me to understand?

------------------------------------------------

My input parameters (partly: relevant to question)

&SYSTEM
  degauss =   2.0000000000d-02
  ecutrho =   3.6000000000d+02
  ecutwfc =   4.5000000000d+01
  ibrav = 0
  A = 8.04590
  nat = 10
  nosym = .true.
  ntyp = 4
  occupations = 'smearing'
  smearing = 'cold'
  input_dft='PBE'
/
&ELECTRONS
conv_thr =         1.0000000000d-08
electron_maxstep = 1080
mixing_beta =      4.0000000000d-01
/
&ions
ion_dynamics = 'bfgs'
/
&CELL
cell_dynamics = 'bfgs'
cell_dofree = 'all'
/
CELL_PARAMETERS {alat}
  1.000000000000000   0.000000000000000   0.000000000000000
  0.000000000000000   1.000000000000000   0.000000000000000
  0.500000000000000   0.500000000000000   0.622894890565381
ATOMIC_SPECIES

OUTPUT (from vc-relaxed)

CELL_PARAMETERS (alat= 15.20454743)
   0.907043787  -0.000224450   0.000167008
  -0.000224449   0.907044034   0.000167012
   0.453512311   0.453512433   0.639596537
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