<div dir="ltr"><pre style="color:rgb(0,0,0)">Dear all,</pre><pre style="color:rgb(0,0,0)"><br></pre><pre style="color:rgb(0,0,0)">I have a problem.</pre><pre style="color:rgb(0,0,0)"><pre>My problem of the 16 atom supercell system ( one-dimension system ), I am trying to vc-relax.</pre>
<pre>First, when it calculates in a supercell, is it amusing that pressure is applied from a vacuum layer? (My calculation is x and y)
</pre><div>Then, if cell_dofree = 'xyz' is used, a vacuum layer will become small rapidly. </div><pre>Does my calculation have any problems? <br></pre><pre><br></pre><pre style>Thanks,</pre><pre style>REI</pre><pre>
<br></pre><pre style>---input----</pre><pre> &control
calculation='vc-relax'
! restart_mode='restart',
tprnfor = .true.
tstress = .true.
prefix='110',
pseudo_dir = './',
outdir='./'
forc_conv_thr = 1.d-6
etot_conv_thr = 1.d-7,
nstep =100000
/
&system
ibrav=6,
celldm(1) = 40.50311907 ,
celldm(3) = 0.180919129 ,
! celldm(3) = 4.362274784 ,
nat= 14,
ntyp= 2,
ecutwfc =80.0,
/
&electrons
diagonalization = 'cg'
electron_maxstep = 100
conv_thr = 1.0d-12,
mixing_beta = 0.2,
/
&ions
bfgs_ndim = 3,
/
&cell
cell_dofree = 'xyz' ,
press_conv_thr=0.1
/
ATOMIC_SPECIES
Si 28.086 Si.pz-vbc.UPF
H 1.00782503207 H.pz-vbc.UPF
ATOMIC_POSITIONS bohr
Si 6.680764370 8.898916109 5.986070989
Si 9.029846753 5.231537887 5.363083201
Si 6.680057629 1.564614309 5.986065052
Si 4.221207325 8.899147367 2.313388654
Si 1.871413129 5.232223481 2.936367832
Si 4.220504860 1.564853884 2.313381924
H 8.432421873 11.126743390 6.027800731
H 2.468854211 -0.662974560 2.271647941
H 2.469974729 11.127305994 2.271650709
H 8.431281864 -0.663551556 6.027799087
H -0.711612701 5.232463267 1.803772875
H 1.465680126 5.232255329 5.753598846
H 11.612877425 5.231282938 6.495661694
H 9.435578196 5.231491779 2.545852436
K_POINTS AUTOMATIC
1 1 16 0 0 0
</pre><pre><br></pre><pre style>----out---</pre><pre style>End of self-consistent calculation (1st)<br></pre><pre><br></pre><pre> Forces acting on atoms (Ry/au):
atom 1 type 1 force = 0.00071410 -0.00000410 -0.00142446
atom 2 type 1 force = -0.00001708 -0.00000009 0.00002541
atom 3 type 1 force = 0.00071411 0.00000383 -0.00142427
atom 4 type 1 force = -0.00071399 -0.00000387 0.00142421
atom 5 type 1 force = 0.00001749 -0.00000012 -0.00002556
atom 6 type 1 force = -0.00071385 0.00000384 0.00142444
atom 7 type 2 force = -0.00000630 0.00001150 -0.00001010
atom 8 type 2 force = 0.00000525 -0.00001238 0.00001021
atom 9 type 2 force = 0.00000578 0.00001223 0.00001025
atom 10 type 2 force = -0.00000582 -0.00001178 -0.00001017
atom 11 type 2 force = 0.00000849 0.00000033 0.00008510
atom 12 type 2 force = 0.00002293 0.00000018 -0.00015858
atom 13 type 2 force = -0.00000777 0.00000016 -0.00008445
atom 14 type 2 force = -0.00002335 0.00000029 0.00015797
Total force = 0.003197 Total SCF correction = 0.000003
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= -0.04
-0.00000100 0.00000000 -0.00000056 -0.15 0.00 -0.08
0.00000000 -0.00000123 0.00000000 0.00 -0.18 0.00
-0.00000056 0.00000000 0.00000137 -0.08 0.00 0.20
BFGS Geometry Optimization
number of scf cycles = 1
number of bfgs steps = 0
enthalpy new = -56.6087703516 Ry
new trust radius = 0.0015934376 bohr
new conv_thr = 1.0E-12 Ry
new unit-cell volume = 12020.99795 a.u.^3 ( 1781.32809 Ang^3 )
CELL_PARAMETERS (alat= 40.50311907)
0.999975086 0.000000000 0.000000000
0.000000000 0.999969153 0.000000000
0.000000000 0.000000000 0.180925314
</pre><div><br></div><div>.</div><div>.</div><div>.</div><div>.</div><div>.</div><div>.</div><div><br></div><div> convergence has been achieved in 23 iterations
Forces acting on atoms (Ry/au):
atom 1 type 1 force = -0.00084136 -0.00000934 0.00019350
atom 2 type 1 force = 0.00123190 0.00000559 -0.00086972
atom 3 type 1 force = -0.00083919 0.00001228 0.00019786
atom 4 type 1 force = 0.00082726 -0.00000351 -0.00021029
atom 5 type 1 force = -0.00119362 0.00000327 0.00087791
atom 6 type 1 force = 0.00082026 0.00000764 -0.00020660
atom 7 type 2 force = 0.00026679 0.00151209 0.00020469
atom 8 type 2 force = -0.00028847 -0.00152297 -0.00020306
atom 9 type 2 force = -0.00029007 0.00152036 -0.00019835
atom 10 type 2 force = 0.00026667 -0.00151682 0.00020223
atom 11 type 2 force = -0.00233462 -0.00000163 -0.00033732
atom 12 type 2 force = 0.00005723 -0.00000321 0.00072011
atom 13 type 2 force = 0.00236998 -0.00000223 0.00035771
atom 14 type 2 force = -0.00005277 -0.00000150 -0.00072867
Total force = 0.005428 Total SCF correction = 0.000022
entering subroutine stress ...
total stress (Ry/bohr**3) (kbar) P= 0.39
0.00000356 0.00000000 -0.00000051 0.52 0.00 -0.07
0.00000000 0.00000351 0.00000000 0.00 0.52 0.00
-0.00000051 0.00000000 0.00000096 -0.07 0.00 0.14
number of scf cycles = 41
number of bfgs steps = 40
enthalpy old = -56.6116889092 Ry
enthalpy new = -56.6119066116 Ry
CASE: enthalpy_new < enthalpy_old
new trust radius = 0.6689834520 bohr
new conv_thr = 1.0E-12 Ry
new unit-cell volume = 7857.03979 a.u.^3 ( 1164.29316 Ang^3 )
CELL_PARAMETERS (alat= 40.50311907)
0.805107566 0.000000000 0.000000000
0.000000000 0.809022136 0.000000000
0.000000000 0.000000000 0.181542885
</div><div><br></div><div><br></div></pre></div>