The ABINIT Users Mailing List ( CLOSED )

[kxyhu@yahoo.com.cn]

Hello,

When I use ABINIT 3.2.1 calculate the 5-0 nanotube ,the space is P1 (#1) in 
the output file.  However when use ABINIT 4.1.3 ,the space group is Pmm2 
(#25). What  is my mistak ?
This is my input file:


# Crystalline 5_0 NanoTube
#
# Computation of the band structure.
# First, a SCF density computation, then a non-SCF band structure calculation.

ndtset 2

#Dataset 1 : usual self-consistent calculation
kptopt1 1          # Option for the automatic generation of k points,
                   # taking into account the symmetry
nshiftk1 1
shiftk1  0.0 0.0 0.5  # These shifts will be the same for all grids
         
ngkpt1  1 1 5
prtden1  1         # Print the density, for use by dataset 2
toldfe1  1.0d-6

#Dataset 2 : the band structure
iscf2    -2
getden2  -1
kptopt2  -3
nband2   70
ndivk2   40 2 1    # 10, 12 and 17 divisions of the 3 segments, delimited
                       # by 4 points.
kptbounds2  0.0  0.0  0.0 # G point
            0.0  0.0  0.5 # Z point 
            0.0  0.5  0.5 # A point
            0.0  0.5  0.0 # F point
           
tolwfr2  1.0d-12
enunit2  1             # Will output the eigenenergies in eV 


#Definition of the unit cell
acell 37.807183 37.807183 8.052930  # 20A 20A 4.26A
#rprim  1.0  0.0  0.0   # Hexgonal primitive vectors (to be scaled by acell)
#       -0.5  0.866025  0.0   
#       0.0  0.0  1.0
angdeg 90.00 90.00 90.00
#Definition of occupation numbers
occopt 4
tsmear 0.04
#Definition of the atom types
ntype 1           # There is one type of atom
zatnum 6         # The keyword "zatnum" refers to the atomic number of the 
                  # possible type(s) of atom. The pseudopotential(s) 
                  # mentioned in the "files" file must correspond
                  # to the type(s) of atom. Here, the only type is Silicon.
                         

#Definition of the atoms
natom 20           # There are two atoms
type 20*1         # They both are of type 1, that is, Silicon.
xangst              # This keyword indicate that the location of the atoms
                  # will follow, one triplet of number for each atom
   1.95722     0.00000    -2.00000
   0.60481     1.86142    -2.00000
  -1.58342     1.15042    -2.00000
  -1.58342    -1.15042    -2.00000
   0.60481    -1.86142    -2.00000
   1.58342     1.15042    -2.71000
  -0.60481     1.86142    -2.71000
  -1.95722     0.00000    -2.71000
  -0.60481    -1.86142    -2.71000
   1.58342    -1.15042    -2.71000
   1.58342     1.15042    -4.13000
  -0.60481     1.86142    -4.13000
  -1.95722     0.00000    -4.13000
  -0.60481    -1.86142    -4.13000
   1.58342    -1.15042    -4.13000
   1.95722     0.00000    -4.84000
   0.60481     1.86142    -4.84000
  -1.58342     1.15042    -4.84000
  -1.58342    -1.15042    -4.84000
   0.60481    -1.86142    -4.84000

#Definition of the planewave basis set
ecut 10.25         # Maximal kinetic energy cut-off, in Hartree

#Definition of the SCF procedure
nstep 99          # Maximal number of SCF cycles
diemac 10.0  # For metals,simply put diemac to a very large value(10^6 is OK)


Thank you,
hu