[Pw_forum] On tne optimization error in PbTiO3

[yukihiro_okuno at fujifilm.co.jp]

Dear PWscf Users.

I'm now working the optimization of PbTiO3

But in the process of calculation, my calculation

stopped with an error like below

   CASE: energy_new > energy_old

     new trust radius        =       0.0000499856 bohr

     trust_radius < trust_radius_min

     resetting bfgs history



%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
     from bfgs : error #         1
     bfgs history already reset at previous step

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

     stopping ...


What is wrong and how to treat such an erro?

This is my input file

&control
    calculation  = 'relax',
    restart_mode = 'from_scratch',
    pseudo_dir   = '/home/okuno/PWSCF/espresso-3.1.1/pseudo/',
    outdir       = './',
    forc_conv_thr = 1.0D-5
 /
 &system
    ibrav=6
    celldm(1)=7.36203352272
    celldm(3)=1.07
    nat=5
    ntyp=3
    nbnd=25
    ecutwfc=30.0
    occupations = 'fixed'
    degauss=0.00
 /
 &electrons
    conv_thr = 1e-7,
    mixing_beta=0.3,
 /
&IONS
 ion_dynamics='bfgs'
 bfgs_ndim=3
 pot_extrapolation = "second_order"
 wfc_extrapolation = "second_order"
/
ATOMIC_SPECIES
  Pb    207.2     Pb.vdb.UPF
  Ti    47.867    Ti.vdb.UPF
  O     15.9994   O.vdb.UPF
ATOMIC_POSITIONS {crystal}
Pb       0.000000000   0.000000000   0.000000000
Ti       0.500000000   0.500000000   0.534020000
O        0.000000000   0.500000000   0.611230000
O        0.500000000   0.000000000   0.611230000
O        0.500000000   0.500000000   0.103910000
K_POINTS {automatic}
  4 4 4 1 1 1