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[Doru Torumba <doru.torumba@cea.fr>]

Dear Abinit users,

I am trying to create the alpha-U structure, but for some reason I do not get
the correct space group (Cmcm, #63). In this structure there are 2 atoms per
unit cell. Atomic positions are (y,-y,-1/4) and (-y,y,1/4) in units of Bravais
lattice vectors defined by (a/2,-b/2,0),  (a/2,b/2,0), (0,0,c). Instead I get
the space group  P2_1/m (#11). Most probably I am overlooking something
obvious, but I can't figure out what. Suggestions are welcome :)

#Definition of the unit cell
acell 5.39 11.1034 9.3247

rprim  0.5  0.5  0.0   # primitive vectors 
          -0.5  0.5  0.0
           0.0  0.0  1.0

#Definition of the atom types
ntypat 1          # No of atom types
znucl 92

#Definition of the atoms
natom 2                           # No of atoms in the cell
typat 1 1                         # Type of each atom

xred
    0.10 -0.10  -0.25
   -0.10  0.10   0.25

#Definition of the planewave basis set
ecut 35       
pawecutdg 40

#Exchange-correlation functional
ixc 11 #GGA (PBE)

#Definition of the k-point grid
kptopt 1

ngkpt 2 2 2
tsmear 0.001

#Spin polarization
nsppol 1

#Definition of occupation numbers
occopt 3
nband 40

#Definition of the SCF procedure
nstep 100
usepaw 1
toldfe 1.0d-6
iscf 7