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Silicene is a 2D material and you have vacuum between its periodic
repetitions.<br>
Therefore the sawtooth potential (tefield=.true.) is also a viable
solution. Have you tried that?<br>
<br>
HTH<br>
<br>
GS<br>
<br>
On 01/10/2015 06:41 PM, siham Sadki wrote:<br>
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<div dir="ltr">Dear all,<br>
<br>
I am wanting to get the Dos of silicene under the effect of an<br>
external electric field. I have done the scf calculations
without<br>
electric field , then again did the scf calculation with an
electric<br>
field included in the z-direction (with value 0.008ua). But
the<br>
convergence is not achieved and it stopped after 100
iterations and<br>
giving it this message:<br>
<br>
"convergence NOT achieved after 100 iterations: stopping"<br>
<br>
You will find below in file for the scf calculation when an<br>
electric field is applied:<br>
&control<br>
calculation = 'scf'<br>
restart_mode='from_scratch',<br>
prefix='Si11ca00E0.008',<br>
lelfield=.true.,<br>
nberrycyc=3<br>
gdir=3<br>
pseudo_dir
='/home/siham/Desktop/espresso-5.0.1-GPU/pseudo',<br>
outdir='/home/siham/Desktop/espresso-5.0.1-GPU/tmp'<br>
/<br>
&system<br>
ibrav= 4,<br>
celldm(1)=7.3103,<br>
celldm(3)= 5,<br>
nat= 2, ntyp= 1,<br>
ecutwfc = 50.0,<br>
ecutrho =370.0<br>
nbnd = 12,<br>
/<br>
&electrons<br>
conv_thr = 1.0d-8<br>
mixing_beta = 0.2<br>
efield_cart(1)=0.d0, efield_cart(2)=0.d0,
efield_cart(3)=0.008d0<br>
/<br>
&ions<br>
/<br>
ATOMIC_SPECIES<br>
Si 28.086 Si.pbe-rrkj.UPF<br>
ATOMIC_POSITIONS (Angstrom)<br>
Si 0.000000000 0.000000000 2.001457804<br>
Si -0.000000019 2.233446401 2.447251213<br>
K_POINTS {automatic}<br>
10 10 1 1 1 1<br>
Thanks in advance<br>
<br>
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