[Pw_forum] difficulties with 'ortho'

[Silviu Zilberman]

Dear All,

I have been testing the cvs version on an IBM Blue Gene machine. In some 
cases everything works fine, but in many other I keep having 
difficulties with the 'ortho' procedures in CP.

Below is a small example for a single water molecule in vacuum. I keep 
getting error messages like:

 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
     from ortho : error #         1
     ortho went bananas
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

In some (other) cases I got error #1 with the same info. I read in the 
source code that under AIX it results from a test to trap NaN's. I tried 
reducing the time step to 1au, but nothing helped. Any ideas?

In addition, did anyone get PW (cvs version) to work on AIX?

Thanks, Silviu.

  &CONTROL
    calculation='cp',
    restart_mode = 'from_scratch',
    nstep  = 1000,
    iprint = 10000,
    isave  = 25000,
    dt     = 1.0,
    pseudo_dir = '$PSEUDO_DIR',
    outdir = '$TMP_DIR',
    prefix = '$PREFIX',
 /
  &SYSTEM
    ibrav = 1,
    celldm(1) = 25.0d0,
    nat = 3,
    ntyp = 2,
    ecutwfc =30.0,
    ecutrho =180.0,
    nr1b=18, nr2b=18,  nr3b=18,
    nspin=2,
    nelec=8,
    nelup=4,
    neldw=4,
  /
 &ELECTRONS
    emass = 700.d0,
    emass_cutoff = 0.8,
    orthogonalization = 'ortho',
    ortho_eps = 1.e-6,
    ortho_max = 100,
    electron_dynamics= 'damp',
    electron_damping =0.20,
    electron_velocities = 'zero',
 /
 &IONS
    ion_dynamics = 'none',
    ion_damping = 0.001
  /
AUTOPILOT
    on_step = 10  : dt = 10
    on_step = 20  : dt = 15
    on_step = 100 : dt = 7
    on_step = 100 : ion_dynamics = 'damp'
ENDRULES
ATOMIC_SPECIES
   O  15.9994 008-O-gpbe--bm.van
   H   1.0079 001-H-gpbe--bm.van
ATOMIC_POSITIONS angstrom
O     3.385583554     8.277954564     7.514590360
H     3.406852766     7.183986045     7.401542108
H     4.359644270     8.695739475     7.220207334
EOF