I am not sure if my results are correct?

[biao]

I spend a bit of time to calculate the total energy at different volume, enen if I tried V=140, I only have left part of the curve. It will take too much computation if I want to try larger volumes (in fact my calculation was killed when I tried to calculate V=154). My calculated E-V:

E = 140.2981172814344, 120.28809830416984, 114.06756557637213, 108.0652743643456, 96.69982780790791, 91.32887812364783, 87.5327434424279, 70.04413761977843, 68.30053221722955, 67.4359788449554, 64.06964145071038, 59.188268228105144, 56.0496680665031, 53.24718466317795, 50.44470125985279, 47.64221785652764, 44.83973445320248
V = -1474.00276740, -1473.78092300, -1473.66315233, -1473.51831104, -1473.13177389, -1472.88049210, -1472.66810184, -1471.12767137, -1470.90084572, -1470.78167218, -1470.26956157, -1469.36448371, -1468.65348969, -1467.91022519, -1467.04176191, -1466.01971867,-1464.80665717

[biao]

I found the problem

I used the FINDSYM to make a new cif and used the cif2cell to make an input file, the input file looks like this:

&CONTROL
calculation=’scf’,
outdir=’.’,
prefix=’FeAl96′,
pseudo_dir=’/home/max/workQE/my_pseudo’,
verbosity=’low’,
tprnfor=.true.,
tstress=.true.,
/
&SYSTEM
ibrav = 0
A = 5.3
nat = 8
ntyp = 2
ecutwfc=70,
ecutrho=700,
input_dft=’pbe’,
occupations=’smearing’,
smearing=’mv’,
degauss=0.005d0,
/
&ELECTRONS
conv_thr=1d-08,
mixing_beta=0.7d0,
/
CELL_PARAMETERS {alat}
1.000000000000000 0.000000000000000 0.000000000000000
0.000000000000000 1.060667434561135 0.000000000000000
0.000000000000000 0.000000000000000 0.612376980364380
ATOMIC_SPECIES
Fe 55.84500 Fe.pbe-spn-kjpaw_psl.0.2.1.UPF
Al 26.98100 Al.pbe-n-kjpaw_psl.1.0.0.UPF
ATOMIC_POSITIONS {crystal}
Fe 0.250000000000000 0.083330000000000 0.250000000000000
Fe 0.750000000000000 0.583330000000000 0.750000000000000
Fe 0.750000000000000 0.916670000000000 0.750000000000000
Fe 0.250000000000000 0.416670000000000 0.250000000000000
Al 0.250000000000000 0.583330000000000 0.750000000000000
Al 0.750000000000000 0.083330000000000 0.250000000000000
Al 0.750000000000000 0.416670000000000 0.250000000000000
Al 0.250000000000000 0.916670000000000 0.750000000000000
K_POINTS {automatic}
6 4 4 0 0 0
This input gives the above results

Then I used the cif2cell directly convert the cif provided and the input looks like this:
&CONTROL
calculation=’scf’,
outdir=’.’,
prefix=’FeAl44_p1′,
pseudo_dir=’/home/max/workQE/my_pseudo’,
verbosity=’low’,
tprnfor=.true.,
tstress=.true.,
/

&SYSTEM
ibrav = 0
A = 2.5121
nat = 4
ntyp = 2
ecutwfc=70,
ecutrho=700,
input_dft=’pbe’,
occupations=’smearing’,
smearing=’mv’,
degauss=0.005d0,
/

&ELECTRONS
conv_thr=1d-08,
mixing_beta=0.7d0,
/

CELL_PARAMETERS {alat}
1.000000000000000 0.000000000000000 0.000000000000000
0.000000000000000 1.632981042829164 0.000000000000000
0.000000000000000 0.000000000000000 1.732049813384575

ATOMIC_SPECIES
Fe 55.84500 Fe.pbe-spn-kjpaw_psl.0.2.1.UPF
Al 26.98100 Al.pbe-n-kjpaw_psl.1.0.0.UPF

ATOMIC_POSITIONS {crystal}
Fe 0.750000000000000 0.750000000000000 0.916666667000000
Fe 0.250000000000000 0.250000000000000 0.083333333000000
Al 0.250000000000000 0.750000000000000 0.416666667000000
Al 0.750000000000000 0.250000000000000 0.583333333000000

K_POINTS {automatic}
6 4 4 0 0 0

The new input works very well

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