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[asubedi <asubedi@gmail.com>]

Dear abiniters,

I have been trying to relax the atomic positions of BaGa2H2 which has
trigonal structure (P-3m1, 164). In Ref 1, the relaxed atomic
positions are given as Ba (0 0 0), Ga (1/3 2/3 0.4703)  and H (1/3 2/3
0.1287). These positions are close to the experimnetal ones that they
determined in the paper. However, Abinit gives very different result:
Ba (0 0 0), Ga (1/3 2/3  0.76) and H (1/3 2/3 0.097). I have done the
calculations with WIEN2K and VASP as well, both of them giving results
very close to the one in Ref 1. What could be going wrong with my
Abinit calculation? I am using the following input file.

## Begin input file
# Define the methodology to find the minimum
ionmov   2
ntime    30
tolmxf   1.0d-7

natfix   1
iatfix   1

toldff   5.0d-8

###########################################################################
# Common input variables

# Definition of the unit cell
  acell     2*8.5669 9.2767

  angdeg    90  90  120
  spgroup   164

# Definition of the atom types
  ntypat    3
  znucl     56  31  1

# Definition of the atoms
  natom     5
  natrd     3
  typat     1  2  3

  xred      0.0000  0.0000  0.0000
            1/3     2/3     0.6703
            1/3     2/3     0.2287

  nband     5

  ixc       11

# Definition of the planewave basis set
  ecut      25.0
#  ecutsm    0.5

# Definition of the k-point grid
  ngkpt     4  4  4
  nshiftk   1
  shiftk    0.0  0.0  0.5

# Definition of the SCF procedure
  iscf      3
#  nline     100
  nstep     800
  diemac    9.0
#  tolvrs   1.0d-18
## End input file

Thanks,
Alaska

1.  Bjorling, Noreus, Haussermann, J. Am. Chem. Soc, vol 128, no 3, 2006 (819)