[QE-users] phonon linewidth calculation
Ivan Dario Arellano Ramirez
arellano at utp.edu.co
Mon Jun 9 11:05:00 CEST 2025
Dear Lorenzo,
I tried the settings you suggested:
nmix_ph=10
alpha_mix=.25
and conv_thr = 1.0d-12 for scf calculation
however, the phonon calculation using ph.x still fails to converge.
I then increased the nmix_ph up to 20 and decreased the alpha_mix up to .1
but the issue persists.
El sáb, 7 jun 2025 a las 7:14, Lorenzo Paulatto (<lorenzo.paulatto at cnrs.fr>)
escribió:
> Hhelo,
>
> increase nmix_ph and reduce alpha_mix, in a difficult case recently I have
> used:
>
> nmix_ph=10
> alpha_mix=.25
>
> Also, the convergence of the scf process in pw.x should be tighter,
> something like
> conv_thr = 1.0d-12
>
> Because the total energy is variational, but the phonons are not, they
> converge much slower with this threshold.
>
> hth
>
>
>
> On 06/06/2025 21:48, Ivan Dario Arellano Ramirez wrote:
>
> I QE users
>
> I want to calculate the phonon linewidth for InN. I am following two
> tutorials. However, in both cases, I encounter the same issue: no
> convergence when using the ph.x module.
>
> Pert. # 1: Fermi energy shift (Ry) = -5.5393E+02 0.0000E+00
>
> iter # 150 total cpu time : 13815.8 secs av.it.: 5.3
> thresh= 4.679E-04 alpha_mix = 0.700 |ddv_scf|^2 = 4.318E-06
>
> End of self-consistent calculation
>
> No convergence has been achieved
>
>
> This is an overview of the two approaches I followed:
>
> 1) perform very dense scf calculation with la2F=.true. in &systems
> (Likely, I am exceeding the maximum of 40000 k points)
> 2) normal scf on coarser k-mesh
> 3) phonon calculation using ph.x
> 4) Inverse Fourier transform of dynamical matrix and the phonon linewidth
> using q2r.x
> 5) Fourier transform to obtain dynamical matrix and the phonon linewidth
> using matdyn.x
>
> The other tutorial proposed an initial scf calculation followed by an nscf
> calculation with la2F=.true. the rest of steps are the same.
>
> Here are all the inputs.
>
> Any suggestions or insights would be greatly appreciated.
>
>
> 1) very dense k-mesh scf
>
> &control
> calculation = 'scf'
> restart_mode='from_scratch',
> prefix='inn_ep',
> tstress = .true.
> tprnfor = .true.
> pseudo_dir = '/home/pps/pbe.0.3.1/PSEUDOPOTENTIALS/',
> outdir='./tmp'
> verbosity = 'high'
> etot_conv_thr = 1.d-6
> forc_conv_thr = 1.d-5
> /
> &system
> ibrav = 0,
> nat= 4,
> ntyp= 2,
> ecutwfc = 90,
> ecutrho = 900,
> occupations='smearing',
> smearing='m-v',
> degauss=0.02,
> la2F = .true.
> /
> &electrons
> conv_thr = 1.0d-8
> electron_maxstep = 200,
> mixing_mode = 'plain'
> mixing_beta = 0.3D0
> diagonalization = 'david'
> /
> ATOMIC_SPECIES
> In 114.818 In.pbe-dn-rrkjus_psl.1.0.0.UPF
> N 14.007 N.pbe-n-rrkjus_psl.1.0.0.UPF
> CELL_PARAMETERS angstrom
> 1.793358573 -3.106188164 0.000000000
> 1.793358573 3.106188164 0.000000000
> 0.000000000 0.000000000 5.799337066
>
> ATOMIC_POSITIONS crystal
> In 0.3333330000 0.6666670000 -0.0019331848
> In 0.6666670000 0.3333330000 0.4980668152
> N 0.3333330000 0.6666670000 0.3767331848
> N 0.6666670000 0.3333330000 0.8767331848
> K_POINTS automatic
> 45 45 36 0 0 0
>
> 2) normal scf
>
> &control
> calculation = 'scf'
> restart_mode='from_scratch',
> prefix='inn_ep',
> tstress = .true.
> tprnfor = .true.
> pseudo_dir = '/home/pps/pbe.0.3.1/PSEUDOPOTENTIALS/',
> outdir='./tmp'
> verbosity = 'high'
> etot_conv_thr = 1.d-6
> forc_conv_thr = 1.d-5
> /
> &system
> ibrav = 0,
> nat= 4,
> ntyp= 2,
> ecutwfc = 90,
> ecutrho = 900,
> occupations='smearing',
> smearing='m-v',
> degauss=0.02,
> /
> &electrons
> conv_thr = 1.0d-8
> electron_maxstep = 200,
> mixing_mode = 'plain'
> mixing_beta = 0.3D0
> diagonalization = 'david'
> /
> ATOMIC_SPECIES
> In 114.818 In.pbe-dn-rrkjus_psl.1.0.0.UPF
> N 14.007 N.pbe-n-rrkjus_psl.1.0.0.UPF
> CELL_PARAMETERS angstrom
> 1.793358573 -3.106188164 0.000000000
> 1.793358573 3.106188164 0.000000000
> 0.000000000 0.000000000 5.799337066
>
> ATOMIC_POSITIONS crystal
> In 0.3333330000 0.6666670000 -0.0019331848
> In 0.6666670000 0.3333330000 0.4980668152
> N 0.3333330000 0.6666670000 0.3767331848
> N 0.6666670000 0.3333330000 0.8767331848
> K_POINTS automatic
> 15 15 12 0 0 0
>
> 3) phonon calculation
>
> Phonons of InN at G!=0
> &inputph
> tr2_ph = 1.0d-14,
> ldisp = .true.,
> prefix = 'inn_ep',
> recover = .true.
> fildyn = 'inn-ph.dyn',
> fildvscf = 'inndv'
> nq1 = 5,
> nq2 = 5,
> nq3 = 3,
> electron_phonon = 'interpolated'
> el_ph_nsigma = 10
> el_ph_sigma = 0.02
> amass(1) = 114.818,
> amass(2) = 14.007,
> outdir = './tmp'
> /
>
> 4) Inverse Fourier Transform
>
> &INPUT
> fildyn = 'inn-ph.dyn',
> zasr = 'crystal',
> flfrc = 'inn-ph.fc',
> la2F = .true.
> /
>
> 5) Fourier Transform
>
> &input
> asr = 'crystal',
> flfrc = 'inn-ph.fc',
> flfrq = 'inn.band.freq'
> flvec = 'inn.band.modes'
> amass(1) = 114.818,
> amass(2) = 14.007,
> q_in_band_form = .true.
> la2F = .true.
> /
> 8
> 0.0000000000 0.0000000000 0.0000000000 40 ! Gamma
> 0.5000000000 0.0000000000 0.0000000000 25 ! M
> 0.3333333333 0.3333333333 0.0000000000 40 ! K
> 0.0000000000 0.0000000000 0.0000000000 25 ! Gamma
> 0.0000000000 0.0000000000 0.5000000000 40 ! A
> 0.5000000000 0.0000000000 0.5000000000 25 ! L
> 0.3333333333 0.3333333333 0.5000000000 40 ! H
> 0.0000000000 0.0000000000 0.5000000000 1 ! A
>
>
> Best regards,
>
> --
>
> Iván Darío Arellano Ramírez
>
> Profesor Titular Programa de Ingeniería Física
>
> Director Grupo de Investigación en Modelado y Simulación Computacional
>
> Universidad Tecnológica de Pereira
>
> El contenido de este mensaje y sus anexos son únicamente para el uso del
> destinatario y pueden contener información clasificada o reservada. Si
> usted no es el destinatario intencional, absténgase de cualquier uso,
> difusión, distribución o copia de esta comunicación.
>
> _______________________________________________________________________________
> The Quantum ESPRESSO Foundation stands in solidarity with all civilians worldwide who are victims of terrorism, military aggression, and indiscriminate warfare.
> --------------------------------------------------------------------------------
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users at lists.quantum-espresso.orghttps://lists.quantum-espresso.org/mailman/listinfo/users
>
> --
> Dr. Lorenzo Paulatto
> IR IMPMC - CNRS UMR 7590 / Sorbonne Université / MNHN
> phone: +33 (0)1 442 79822 / telegram: lpaulatto
> http://www.impmc.upmc.fr/~paulatto/ - https://anharmonic.github.io/
> 23-24/423 B115, 4 place Jussieu 75252 Paris CX 05
>
> _______________________________________________________________________________
> The Quantum ESPRESSO Foundation stands in solidarity with all civilians
> worldwide who are victims of terrorism, military aggression, and
> indiscriminate warfare.
>
> --------------------------------------------------------------------------------
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users at lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
--
Iván Darío Arellano Ramírez
Profesor Titular Programa de Ingeniería Física
Director Grupo de Investigación en Modelado y Simulación Computacional
Universidad Tecnológica de Pereira
--
El contenido de este mensaje y sus anexos son únicamente para el uso del
destinatario y pueden contener información clasificada o reservada. Si
usted no es el destinatario intencional, absténgase de cualquier uso,
difusión, distribución o copia de esta comunicación.
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