1. Prepare the input file BN.scf.in for the self-consistent scf calculationas follows:

############################BN.scf.in############################

&CONTROL

calculation='scf'

title='BN'

prefix='BN'

restart_mode='from_scratch'

nstep=1000

outdir='./tmp'

pseudo_dir='./'

wf_collect=.true.

tstress=.true.

tprnfor=.true.

/

&SYSTEM

ibrav=0

nat=2

ntyp=2

ecutwfc= 60.0,

ecutrho= 600.0,

input_DFT='PBE',

occupations= 'smearing',

degauss= 1.0d-4,

smearing= 'marzari-vanderbilt',

/

&ELECTRONS

electron_maxstep= 1000,

conv_thr= 1.0d-10,

mixing_mode= 'plain',

mixing_beta= 0.3d0,

scf_must_converge=.true.

/

&IONS

ion_dynamics='bfgs'

ion_positions= 'default'

/

ATOMIC_SPECIES

B10.81 B.pbe-n-van_ak.UPF

N14.01 N.pbe-van_ak.UPF

CELL_PARAMETERS(angstrom)

  2.511218514  0.000000000   0.000000000

 -1.255609257  2.174779027   0.000000000

  0.000000000  0.000000000  10.000000000

ATOMIC_POSITIONS(crystal)

B        0.666666687   0.333333343  0.500000000

N        0.333333313   0.666666627  0.500000000

K_POINTSautomatic

1212 1 0 0 0

#################################################################

2. Launch the calculation with the following command:

$pw.x<BN.scf.in>BN.scf.out