[Pw_forum] BFGS ionic relax: maximum number of steps?

[Xijun Wang]

Hi,

Whenever I run a "restart" relaxation of ions, it always terminated after
one bfgs iteration, and tells me,

   The maximum number of steps has been reached.
   End of BFGS Geometry Optimization
   Begin final coordinates
   ...

Even  I set nstep = 1000 and electron_maxstep = 1000

So, I have to copy all coordinates into a new input to run it
"from_scratch", then it will run normally, terminate after a lot of
iterations.

Anything wrong with my input file?
A compilation error? Or it just means that the convergence has been reached?

Regards,
Xijun Wang


The input file:
*****************

&CONTROL
  calculation   = 'relax',
  restart_mode  = 'restart',
  prefix        = 'trip',
  outdir        = './'
  pseudo_dir    = '/RQusagers/wangxiju/espresso/pseudo'
  etot_conv_thr = 1.0E-6
  forc_conv_thr = 1.0D-5
  tstress       = .true. ,
  tprnfor       = .true. ,
  nstep = 1000 ,
  dt = 150
 /
&SYSTEM
  ibrav = 0, celldm(1) = 19.964957
  nat = 64, ntyp = 2, ecutwfc = 25, ecutrho = 300
  occupations = 'smearing', smearing = 'cold', degauss = 0.03D0
  nspin = 2, tot_magnetization = 2
  nbnd = 340
  /
&ELECTRONS
  diagonalization = 'cg', electron_maxstep = 1000, conv_thr = 1.D-6
  mixing_mode = 'plain', mixing_beta = 0.1D0, mixing_ndim = 16
 /
&IONS
  ion_dynamics = 'bfgs', upscale = 100.D0
/
CELL_PARAMETERS hexagonal
   0.992781869   0.000000000  -0.001946740
   0.000000000   0.588596312   0.000000000
  -0.254396859   0.000000000   1.117512248
ATOMIC_SPECIES
 Zr 91.22400 Zr.pbe-nsp-van.UPF
 N  14.00674  N.pbe-van_bm.UPF
ATOMIC_POSITIONS angstrom
  N 6.239044778 1.554381787 1.967061325
  N 1.558801609 1.554381786 9.815800854
......

-- 
Dept. of Chem and Biochem, Concordia University
7141 Sherbrooke Ouest, Montreal, QC, Canada (H4B 1R6)
Tel: 514-848-2424-#5835 (Lab) TA office: SP175.23
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