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<div><div dir="ltr">Dear QE users<br></div><div dir="ltr">I am trying to calculate the phonon dispersion curves of PdS2 BILAYERS<br></div><div dir="ltr">but it always give negative frequencies of the order of ~ -8 cm-1.<br></div><div dir="ltr">Please have a look at my input file and feel free to edit it to make<br></div><div dir="ltr">it more meaningful<br></div><div dir="ltr">---------------------------------------------------------------------------------------------------------------<br></div><div dir="ltr">&control<br></div><div dir="ltr"> calculation = 'scf',<br></div><div dir="ltr"> restart_mode = 'from_scratch',<br></div><div dir="ltr"> pseudo_dir='~/pseudo_directory',<br></div><div dir="ltr"> outdir='./OUT',<br></div><div dir="ltr"> prefix='PtS2bs0',<br></div><div dir="ltr">/<br></div><div dir="ltr">&system<br></div><div dir="ltr"> ibrav = 4, a = 3.52, b = 3.52, c = 20.0, cosAB = -0.5, cosAC = 0.0,<br></div><div dir="ltr">cosBC = 0.0,<br></div><div dir="ltr"> nat = 6, ntyp = 2,<br></div><div dir="ltr"> ecutwfc = 75,<br></div><div dir="ltr"> ecutrho = 300,<br></div><div dir="ltr"> nbnd = 40,<br></div><div dir="ltr"> occupations = 'smearing', smearing = 'gaussian', degauss = 0.001,<br></div><div dir="ltr"> /<br></div><div dir="ltr">&electrons<br></div><div dir="ltr"> mixing_beta = 0.3,<br></div><div dir="ltr"> conv_thr = 1.0d-9,<br></div><div dir="ltr"> electron_maxstep = 900,<br></div><div dir="ltr">/<br></div><div dir="ltr">ATOMIC_SPECIES<br></div><div dir="ltr">Pt 195.08 Pt.pbe-mt_fhi.UPF<br></div><div dir="ltr">S 32.06 S.pbe-mt_fhi.UPF<br></div><div dir="ltr">ATOMIC_POSITIONS angstrom<br></div><div dir="ltr">Pt 0.00000000 0.00000000 0.00000000<br></div><div dir="ltr">S 1.80374872 1.02665089 1.24494264<br></div><div dir="ltr">S -1.80374872 -1.02665089 -1.24494264<br></div><div dir="ltr">Pt 0.00000000 0.00000000 6.70000000<br></div><div dir="ltr">S 1.80374872 1.02665089 7.94494264<br></div><div dir="ltr">S -1.80374872 -1.02665089 5.45505736<br></div><div dir="ltr">K_POINTS AUTOMATIC<br></div><div dir="ltr">16 16 4 0 0 0<br></div><div dir="ltr">-----------------------------------------------------------------------------<br></div><div dir="ltr">#phonon of unstrained structure<br></div><div dir="ltr">&inputph<br></div><div dir="ltr"> prefix = 'PtS2bs0',<br></div><div dir="ltr"> tr2_ph = 1.0d-16,<br></div><div dir="ltr"> ldisp = .true.,<br></div><div dir="ltr"> search_sym = .false.,<br></div><div dir="ltr"> nq1 = 2, nq2 = 2, nq3 = 1,<br></div><div dir="ltr"> amass(1) = 195.08,<br></div><div dir="ltr"> amass(2) = 32.06,<br></div><div dir="ltr"> outdir = './OUT',<br></div><div dir="ltr"> fildyn = 'PtS2bs0.dyn',<br></div><div dir="ltr">/<br></div><div dir="ltr">----------------------------------------------------------------------------------<br></div><div dir="ltr">&input<br></div><div dir="ltr">fildyn = 'PtS2bs0.dyn',<br></div><div dir="ltr">zasr = 'simple',<br></div><div dir="ltr">flfrc = 'PtS2bs0.fc',<br></div><div dir="ltr">/<br></div><div dir="ltr">-------------------------------------------------------------------------------<br></div><div dir="ltr">&input<br></div><div dir="ltr">asr = 'simple',<br></div><div dir="ltr">amass(1) = 195.08,<br></div><div dir="ltr">amass(2) = 32.06,<br></div><div dir="ltr">flfrc = 'PtS2bs0fc',<br></div><div dir="ltr">flfrq = 'PtS2bs0.freq',<br></div><div dir="ltr">/<br></div><div dir="ltr"> 240<br></div><div dir="ltr"> 0.0000000000 0.0000000000 0.0000000000 1.0<br></div><div dir="ltr"> 0.0057471264 0.0000000000 0.0000000000 1.0<br></div><div dir="ltr"> 0.0114942529 0.0000000000 0.0000000000 1.0<br></div><div dir="ltr"> 0.0172413793 0.0000000000 0.0000000000 1.0<br></div><div dir="ltr"> 0.0229885057 0.0000000000 0.0000000000 1.0<br></div><div dir="ltr"> 0.0287356322 0.0000000000 0.0000000000 1.0<br></div><div dir="ltr">:<br></div><div dir="ltr">:<br></div><div dir="ltr">:<br></div><div dir="ltr">:<br></div></div>
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