[Pw_forum] Phonon calculations failed to converge

Rita Maji rita.maji at niser.ac.in
Thu Oct 26 12:47:10 CEST 2017

```Hi Jibiao,
Tuning of "alpha_mix(niter)" may help you in convergence, so you can try
that.

Thanks,
Rita
NISER, Bhubaneswar
INDIA

On Thu, Oct 26, 2017 at 4:05 PM, jibiaoli <jibiaoli at foxmail.com> wrote:

> Dear all,
>
> I try to calculate phonons at gamma for a fully relaxed
> structure(CO/Fe(100)), but the calculation failed to converge in 100
> interations. Any suggestions to get better results? Thank you very much!
>
>      Calculation of q =    0.0000000   0.0000000   0.0000000
> ...
>      There are  58 irreducible representations
> ...
>      Representation #  1 mode #   1
>
>      Self-consistent Calculation
>
>      Pert. #  1: Fermi energy shift (Ry) =     1.5373E-02    -3.9705E-23
>
>       iter #   1 total cpu time :  2186.1 secs   av.it.:  10.8
>       thresh= 1.000E-02 alpha_mix =  0.700 |ddv_scf|^2 =  1.220E-05
>  ...
>
>      Pert. #  1: Fermi energy shift (Ry) =    -4.1145E+08    -1.3878E-17
>
>       iter #  99 total cpu time :114535.6 secs   av.it.:  76.5
>       thresh= 1.000E-02 alpha_mix =  0.700 |ddv_scf|^2 =  1.192E+16
>      kpoint   3 ibnd 211 solve_linter: root not converged  1.297E-02
>      kpoint   6 ibnd 210 solve_linter: root not converged  2.155E-02
>      kpoint  12 ibnd 166 solve_linter: root not converged  3.906E-02
>      kpoint  13 ibnd 167 solve_linter: root not converged  4.197E-02
>      kpoint  15 ibnd 167 solve_linter: root not converged  1.025E-02
>      kpoint  16 ibnd 167 solve_linter: root not converged  3.094E-02
>      kpoint  17 ibnd 169 solve_linter: root not converged  1.276E-02
>
>      Pert. #  1: Fermi energy shift (Ry) =     1.7443E+09    -5.5511E-17
>
>       iter # 100 total cpu time :116795.0 secs   av.it.:  75.2
>       thresh= 1.000E-02 alpha_mix =  0.700 |ddv_scf|^2 =  1.063E+17
>
>      End of self-consistent calculation
>
>      No convergence has been achieved
>
> Sincerely
>
> Jibiao Li
>
> Yangtze Normal University, China
>
> My input files
> phonons at Gamma
>  &inputph
>   tr2_ph=1.0d-12,
>   prefix='T.1ml',
>   amass(1)=15.999,
>   amass(2)=12.001,
>   amass(3)=55.850,
>   outdir='./',
>   fildyn='T.1ml.dynG',
>  /
> 0.0 0.0 0.0
>
>
>  &CONTROL
>                  calculation = 'scf' ,
>                 restart_mode = 'from_scratch' ,
>                       outdir = './' ,
>                   pseudo_dir = '/home/bmllzr/codes/pseudo/' ,
>                       prefix = 'T.1ml' ,
>                      tstress = .true. ,
>                      tprnfor = .true. ,
>  /
>  &SYSTEM
>                        ibrav = 6,
>                    celldm(1) = 10.847032278,
>                    celldm(3) = 3.5,
>                          nat = 28,
>                         ntyp = 3,
>                      ecutwfc = 35,
>                      ecutrho = 280 ,
>                  occupations = 'smearing' ,
>                      degauss = 0.02D0 ,
>                     smearing = 'methfessel-paxton' ,
>                        nspin = 2 ,
>    starting_magnetization(1) = -0.1,
>    starting_magnetization(2) = -0.1,
>    starting_magnetization(3) = 2.9,
>                     vdw_corr = 'DFT-D',
>  /
>  &ELECTRONS
>                  mixing_beta = 0.2D0 ,
>              diagonalization = 'david' ,
>  /
> &IONS
> /
> ATOMIC_SPECIES
>     O   15.99900  O.pbe-van_ak.UPF
>     C   12.001    C.pbe-van_ak.UPF
>    Fe   55.85000  Fe.pbe-sp-van_ak.UPF
> ATOMIC_POSITIONS angstrom
> C        2.870000022   0.000000000  10.963681264
> O        2.870000002   0.000000000   9.820542707
> C        0.000000000   2.870000002  10.963681264
> O        0.000000000   2.870000002   9.820542707
> O        2.870000022   2.869999989   8.484765130
> C        2.870000002   2.869999976   7.310891865
> O        0.000000000   0.000000000   8.485269386
> C        0.000000000   0.000000000   7.311308054
> Fe      -0.000000001   0.000000000   5.545607710
> Fe       2.870000008   0.000000007   5.773720938
> Fe       0.000000006   2.870000008   5.773720988
> Fe       2.870000000   2.870000009   5.545277888
> Fe       1.435015580   1.435015326   4.303533738
> Fe       4.304984355   1.435015405   4.303533575
> Fe       1.435015640   4.304984586   4.303533577
> Fe       4.304984433   4.304984688   4.303533741
> Fe       0.000000000   0.000000000   2.848495086
> Fe       2.870000000   0.000000000   2.879568308
> Fe       0.000000000   2.870000000   2.879568308
> Fe       2.870000000   2.870000000   2.848497766
> Fe       4.304935556   4.304935556   1.421163132
> Fe       1.435064444   1.435064444   1.421163132
> Fe       4.304935556   1.435064444   1.421163132
> Fe       1.435064444   4.304935556   1.421163132
> Fe       0.000000000   0.000000000   0.066873495
> Fe       2.870000000   0.000000000   0.071056483
> Fe       0.000000000   2.870000000   0.071056483
> Fe       2.870000000   2.870000000   0.066732928
> K_POINTS automatic
>   6 6 1   0 0 0
>
>
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20171026/5f91351a/attachment.html>
```