Il 2020-06-19 10:15 Andrea Urru ha scritto:
Dear Coralie,
the issue you are facing is most likely due to the W pseudopotential,
which gives convergence issues if used in slab systems
with vacuum space, as reported here:
https://dalcorso.github.io/pslibrary/PP_list.html
The behavior you describe might be due to a ghost state, but I am not
deeply expert in pseudopotentials and I cannot swear.
I would suggest you to try a different pseudopotential. If you wish to
use Ultrasoft pseudopotentials you may try the one from
Pslibrary 0.3.1.
Best regards,
Andrea Urru
Ph. D. Student in Condensed Matter
SISSA - Trieste (Italy)
Il giorno 17 giu 2020, alle ore 23:31, Coralie Khabbaz
<[email protected]> ha scritto:
Hello,
I am doing an scf calculation on a tungsten nitride (WN) slab
(catalyst), with a methane molecule 5 Angstrom away from the
surface. The energy values are not converging, even after 533
iterations. The energy values are very negative, and then they
increase to a positive value then decrease a lot again. Before
building the supercell, I had a WN unit cell with 433 K-points.
Then, I built the super cell by using a scaling of 333 and miller
indices of 100. I tried using K points of 111 and 222 for my super
cell, but the calculations didn't converge for both.
This is the input file I am using:
&CONTROL
calculation = "scf"
max_seconds = 1.72800e+05
pseudo_dir =
"/home/coralee/projects/def-jkopysci/coralee/.pseudopot"
restart_mode = "from_scratch"
/
&SYSTEM
a = 1.24907e+01
angle1(1) = 0.00000e+00
angle1(2) = 0.00000e+00
angle2(1) = 0.00000e+00
angle2(2) = 0.00000e+00
b = 1.34803e+01
c = 2.52767e+01
cosab = 6.12323e-17
cosac = 6.12323e-17
cosbc = -1.85547e-01
degauss = 1.00000e-02
ecutrho = 4.50000e+02
ecutwfc = 5.00000e+01
ibrav = 14
nat = 113
nspin = 2
ntyp = 4
occupations = "smearing"
smearing = "gaussian"
starting_magnetization(1) = 2.00000e-01
starting_magnetization(2) = 6.00000e-01
starting_magnetization(3) = 0.00000e+00
starting_magnetization(4) = 0.00000e+00
/
&ELECTRONS
conv_thr = 1.00000e-06
diagonalization = "david"
electron_maxstep = 528
mixing_beta = 4.00000e-01
startingpot = "atomic"
startingwfc = "atomic+random"
/
K_POINTS {automatic}
4 4 2 0 0 0
ATOMIC_SPECIES
N 14.00674 N.pbe-n-rrkjus_psl.1.0.0.UPF
W 183.84000 W.pbe-spn-rrkjus_psl.1.0.0.UPF
C 12.01070 C.pbe-n-rrkjus_psl.1.0.0.UPF
H 1.00794 H.pbe-rrkjus_psl.1.0.0.UPF
ATOMIC_POSITIONS {angstrom}
N 2.481849 0.418242 14.837784
N 6.645429 0.418242 14.837784
N 10.809008 0.418242 14.837784
N 2.481849 4.911686 14.837784
N 6.645429 4.911686 14.837784
N 10.809008 4.911686 14.837784
N 2.481849 9.405131 14.837784
N 6.645429 9.405131 14.837784
N 10.809008 9.405131 14.837784
W 2.481849 2.628097 14.748648
W 6.645429 2.628097 14.748648
W 10.809008 2.628097 14.748648
W 2.481849 7.121541 14.748648
W 6.645429 7.121541 14.748648
W 10.809008 7.121541 14.748648
W 2.481849 -1.865347 14.748648
W 6.645429 -1.865347 14.748648
W 10.809008 -1.865347 14.748648
N 0.400059 3.110895 14.468179
N 4.563639 3.110895 14.468179
N 8.727218 3.110895 14.468179
N 0.400059 7.604339 14.468179
N 4.563639 7.604339 14.468179
N 8.727218 7.604339 14.468179
N 0.400059 -1.382549 14.468179
N 4.563639 -1.382549 14.468179
N 8.727218 -1.382549 14.468179
W 0.400059 0.783425 14.415413
W 4.563639 0.783425 14.415413
W 8.727218 0.783425 14.415413
W 0.400059 5.276869 14.415413
W 4.563639 5.276869 14.415413
W 8.727218 5.276869 14.415413
W 0.400059 9.770314 14.415413
W 4.563639 9.770314 14.415413
W 8.727218 9.770314 14.415413
N 2.481849 3.081849 12.630078 0 0 0
N 6.645429 3.081849 12.630078 0 0 0
N 10.809008 3.081849 12.630078 0 0 0
N 2.481849 7.575293 12.630078 0 0 0
N 6.645429 7.575293 12.630078 0 0 0
N 10.809008 7.575293 12.630078 0 0 0
N 2.481849 -1.411595 12.630078 0 0 0
N 6.645429 -1.411595 12.630078 0 0 0
N 10.809008 -1.411595 12.630078 0 0 0
W 2.481849 0.798260 12.540942 0 0 0
W 6.645429 0.798260 12.540942 0 0 0
W 10.809008 0.798260 12.540942 0 0 0
W 2.481849 5.291704 12.540942 0 0 0
W 6.645429 5.291704 12.540942 0 0 0
W 10.809008 5.291704 12.540942 0 0 0
W 2.481849 9.785148 12.540942 0 0 0
W 6.645429 9.785148 12.540942 0 0 0
W 10.809008 9.785148 12.540942 0 0 0
N 0.400059 1.281057 12.260473 0 0 0
N 4.563639 1.281057 12.260473 0 0 0
N 8.727218 1.281057 12.260473 0 0 0
N 0.400059 5.774502 12.260473 0 0 0
N 4.563639 5.774502 12.260473 0 0 0
N 8.727218 5.774502 12.260473 0 0 0
N 0.400059 10.267946 12.260473 0 0 0
N 4.563639 10.267946 12.260473 0 0 0
N 8.727218 10.267946 12.260473 0 0 0
W 0.400059 3.447032 12.207706 0 0 0
W 4.563639 3.447032 12.207706 0 0 0
W 8.727218 3.447032 12.207706 0 0 0
W 0.400059 7.940476 12.207706 0 0 0
W 4.563639 7.940476 12.207706 0 0 0
W 8.727218 7.940476 12.207706 0 0 0
W 0.400059 -1.046412 12.207706 0 0 0
W 4.563639 -1.046412 12.207706 0 0 0
W 8.727218 -1.046412 12.207706 0 0 0
N 2.481849 1.252012 10.422372 0 0 0
N 6.645429 1.252012 10.422372 0 0 0
N 10.809008 1.252012 10.422372 0 0 0
N 2.481849 5.745456 10.422372 0 0 0
N 6.645429 5.745456 10.422372 0 0 0
N 10.809008 5.745456 10.422372 0 0 0
N 2.481849 10.238900 10.422372 0 0 0
N 6.645429 10.238900 10.422372 0 0 0
N 10.809008 10.238900 10.422372 0 0 0
W 2.481849 3.461867 10.333236 0 0 0
W 6.645429 3.461867 10.333236 0 0 0
W 10.809008 3.461867 10.333236 0 0 0
W 2.481849 7.955311 10.333236 0 0 0
W 6.645429 7.955311 10.333236 0 0 0
W 10.809008 7.955311 10.333236 0 0 0
W 2.481849 -1.031577 10.333236 0 0 0
W 6.645429 -1.031577 10.333236 0 0 0
W 10.809008 -1.031577 10.333236 0 0 0
N 0.400059 3.944664 10.052766 0 0 0
N 4.563639 3.944664 10.052766 0 0 0
N 8.727218 3.944664 10.052766 0 0 0
N 0.400059 8.438108 10.052766 0 0 0
N 4.563639 8.438108 10.052766 0 0 0
N 8.727218 8.438108 10.052766 0 0 0
N 0.400059 -0.548780 10.052766 0 0 0
N 4.563639 -0.548780 10.052766 0 0 0
N 8.727218 -0.548780 10.052766 0 0 0
W 0.400059 1.617195 10.000000 0 0 0
W 4.563639 1.617195 10.000000 0 0 0
W 8.727218 1.617195 10.000000 0 0 0
W 0.400059 6.110639 10.000000 0 0 0
W 4.563639 6.110639 10.000000 0 0 0
W 8.727218 6.110639 10.000000 0 0 0
W 0.400059 10.604083 10.000000 0 0 0
W 4.563639 10.604083 10.000000 0 0 0
W 8.727218 10.604083 10.000000 0 0 0
C 10.809008 2.628097 19.750000
H 10.177000 1.997000 20.383000
H 11.443000 1.997000 19.117000
H 10.177000 3.263000 19.117000
H 11.443000 3.263000 20.383000
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Quantum ESPRESSO is supported by MaX
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Dear All,
As Andrea mentioned before, the PBE-ultrasoft pseudos for W found in
PSlibrary 1.0.0 are not working for 2D geometries.
However, I had similar convergence issues also using W pseudos taken
from older versions of PSlibrary (both scalar and fully relativistic),
especially if lattice relaxation was included in the calculation.
I solved the problem by using the pseudopotentials found here:
https://www.materialscloud.org/discover/sssp/table/efficiency
best,
Mattia Angeli
Ph. D. Student in Condensed Matter
SISSA - Trieste (Italy)
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users mailing list [email protected]
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