[Pw_forum] Regarding ph.x

[Manu Hegde]

Hello All,

I was trying to calculate phonon dispersion in PbTIO3, my SCF calculations
went well, but I am struggling with ph.x. It is taking long time to
converge. Any suggestions to  improve the input and make it faster?.

 Both SCF and Phonon input are below, please have a look.


&CONTROL
                 calculation = 'scf' ,
                restart_mode = 'from_scratch' ,
                      outdir = '/home/user/espresso-5.3.0/PBTIO/' ,
                  pseudo_dir = '/home/user/espresso-5.3.0/pseudo/' ,
                      prefix = 'perov',
                          tstress = .true.,
                         tprnfor = .true.,
                       verbosity = 'high',
 /
 &SYSTEM

                           A = 3.97,
                       space_group = 221,
                         nat = 3,
                        ntyp = 3,
                     ecutwfc = 30.0 ,

 /
 &ELECTRONS
                    conv_thr = 1D-6,
                   mixing_beta=0.3
 /
ATOMIC_SPECIES
   Pb  207.20000  Pb.pz-d-van.UPF
   Ti   47.86700  Ti.pz-sp-van_ak.UPF
    O   15.99940  O.pz-van_ak.UPF
ATOMIC_POSITIONS crystal_sg
   Pb  1a
   Ti  1b  0.5
    O  0.5 0.5 0.0
K_POINTS automatic
  8 8 8   0 0 0


Phonon input


phonons of PbTio at grid
&inputph
        prefix = 'perov'

        ldisp = .true.,
        fildyn = 'pbtio.dyn',
        amass(1) = 207.2,
        amass(2) = 47.867,
        amass(3) = 15.9994
        outdir = '/home/user/espresso-5.3.0/PBTIO/'
        nq1 = 4,
        nq2 = 4,
        nq3 = 4,
        tr2_ph = 1.0d-12,
/



Thanks and Regards,
Manu
University of Waterloo
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20160608/b9a87b3f/attachment.html>