[Pw_forum] vc-relax with nspin=2 . Crashin

[m.g.p.krishna at chem.leidenuniv.nl]

Dear List,

I am trying a bond-length optimization of a simple graphene layer  
using QE v4.3. It works fine when I use nspin=1 but crashes when I  
switch to nspin=2. I already tried with different optmizers (CG and  
BFGS) and file collection methods ('random'...) together. But still  
the error persists. Please see also the input file.

The error messages are:
(using  mpirun -np 128 ~/krishna/MyBin/espresso-4.3/bin/pw.x -npool 8  
< test.spur.in > test.spur.out &):
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
      Writing output data file grapheneSpU.save
      NEW-OLD atomic charge density approx. for the potential
forrtl: severe (174): SIGSEGV, segmentation fault occurred
Image              PC                Routine            Line        Source
libopen-pal.so.0   00002B2FA6EA1BD0  Unknown               Unknown  Unknown
libopen-pal.so.0   00002B2FA6EA05A5  Unknown               Unknown  Unknown
libmpi.so.0        00002B2FA663F0BF  Unknown               Unknown  Unknown
libmpi.so.0        00002B2FA664054D  Unknown               Unknown  Unknown
libmpi.so.0        00002B2FA663EA56  Unknown               Unknown  Unknown
libmpi.so.0        00002B2FA6630D10  Unknown               Unknown  Unknown
libmpi.so.0        00002B2FA66312FB  Unknown               Unknown  Unknown
libmpi.so.0        00002B2FA66739BD  Unknown               Unknown  Unknown
libmpi_f77.so.0    00002B2FA63E500D  Unknown               Unknown  Unknown
pw.x               00000000006B03F1  mp_mp_mp_comm_spl         214  mp.f90
pw.x               0000000000464FAC  paw_onecenter_mp_         114   
paw_onecenter.f90
pw.x               000000000050804C  extrapolate_charg         435   
update_pot.f90
pw.x               0000000000503634  update_pot_               206   
update_pot.f90
pw.x               000000000043DADB  hinit1_                    34  hinit1.f90
pw.x               0000000000433BE9  MAIN__                    203  pwscf.f90
pw.x               000000000043388C  Unknown               Unknown  Unknown
libc.so.6          00000032ED61D974  Unknown               Unknown  Unknown
pw.x               0000000000433799  Unknown               Unknown  Unknown

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
I guess some fishy thing is there in IO w.r.t. spin.
Does any one has Idea about it?

Although It is a simple bond-length optimization test, later this need  
to be changed to some other system for a real production work.

Thanks in advance,

cheers

Krishna Mohan G. P.
Centre for Superfunctional Materials
POSTECH
S. Korea
=====================================================================

&CONTROL
                  calculation = 'vc-relax' ,
                 restart_mode = 'from_scratch' ,
                       outdir = './' ,
                   pseudo_dir = '/home01/a202kks/krishna/myPSP' ,
                       prefix = 'grapheneSpU' ,
                      tprnfor = .true. ,
wf_collect=.true.,
etot_conv_thr=1.0E-4,
forc_conv_thr=1.0E-3,
  /
  &SYSTEM
                        ibrav = 0,
                    celldm(1) = 1.,
                          nat = 2,
                         ntyp = 1,
                      ecutwfc = 30 ,
                      ecutrho = 250 ,
                         nbnd = 16,
                        nosym = .true.,
                   tot_charge = 0.000000,
nspin = 2,
starting_magnetization(1) = 1,
starting_magnetization(2) = 1,
occupations = 'smearing',
smearing      = 'gauss',
degauss       = 0.02,
/
  &ELECTRONS
                     conv_thr = 1.E-4 ,
                  mixing_mode = 'plain' ,
                  mixing_beta = 0.3 ,
              diagonalization = 'cg' ,
startingwfc='file',
startingpot='file',
  /
  &IONS
ion_dynamics='damp',
wfc_extrapolation='second_order',
wfc_extrapolation='second_order',
  /
  &CELL
cell_dynamics = 'damp-pr' ,
cell_factor=3,
cell_dofree='all',
/
CELL_PARAMETERS Hexagonal
    4.025116724967956   2.323902182969979   0.000000000000000
    4.025116724967956  -2.323902182969979   0.000000000000000
    0.000000000000000   0.000000000000000  15.000000000000000
ATOMIC_SPECIES
     C   12.0107  C.pbe-paw_kj.UPF
ATOMIC_POSITIONS angstrom
C      1.420000000000000   0.000000000000000   0.000000000000000
C      2.840000000000000   0.000000000000000   0.000000000000000
  K_POINTS automatic
  8 8 1 1 1 1