Hello!
I'm a fresh user of Q-E so please forgive me for any silly mistakes. I
was browsing the forum archive but I couldn't find any solution for my
problem - i try to make some calculations aboout ferroelectric materials
- polarization via Berry Phase method, which seems to be verry good at
the moment for me. But I need to aplay an electric field and relax the
structure under it's influence to calculte polarization after that. I
try to do that for BaTiO3 and without field it works great but i don't
know what's wrong with my input file, which is:
&CONTROL
calculation = "relax",
restart_mode='from_scratch',
prefix = "bto",
pseudo_dir = "../pseudo",
outdir = "./",
lelfield = .true.,
gdir = 3,
nppstr = 7,
nberrycyc=1
/
&SYSTEM
ibrav=6, celldm(1)=7.541801934, celldm(3)=1.011087586, nat=5, ntyp=3,
degauss=0.00, nbnd=20,
occupations='fixed',
ecutwfc = 20.0,
ecutrho =120.0
/
&ELECTRONS
conv_thr = 1.0d-12,
mixing_beta = 0.7,
efield=0.0001
/
&IONS
ion_dynamics = 'bfgs'
pot_extrapolation = 'second_order'
/
ATOMIC_SPECIES
O 15.9994 O.pw91-van_ak.UPF
Ti 47.867 Ti.pw91-nsp-van.UPF
Ba 137.327 Ba.pw91-nsp-van.UPF
ATOMIC_POSITIONS crystal
Ba 0.0 0.0 0.0
Ti 0.5 0.5 0.5224
O 0.5 0.5 -0.0244
O 0.5 0.0 0.4895
O 0.0 0.5 0.4895
K_POINTS automatic
4 4 4 1 1 1
When i tray to make calculations with that program gaves me such an
answer after
" Self-consistent Calculation
iteration # 1 ecut= 20.00 ryd beta=0.70
Davidson diagonalization with overlap
error hepsiher: translated G= -0.145833333333333
-0.145833333333333
-0.144234125067513 with crystal coordinates 0
0
0 corresponds to ng= 1 but G(ng)=
0.000000000000000E+000 0.000000000000000E+000 0.000000000000000E+000
probably because G_par is NOT a reciprocal lattice vector
Possible choices as smallest G_par: "
what I'm doing wrong? Please help me :) thank you in advance
Dariusz Kajewski