Home › Forums › geometry optimization › step 1 : volume optimization › I am not sure if my results are correct?

Viewing 2 posts - 1 through 2 (of 2 total)
  • Author
    Posts
  • October 31, 2022 at 9:07 am #7508
    biao
    Participant

    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

    October 31, 2022 at 10:48 pm #7536
    biao
    Participant

    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

  • Author
    Posts
Viewing 2 posts - 1 through 2 (of 2 total)
  • You must be logged in to reply to this topic.
Scroll to Top