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[Raghani Pushpa <pushpa@jncasr.ac.in>]

dear users,
i m a new user of abinit. i did one phonon calculation. in that the self
consistency is achieved many times ie. ETOT is converged many times. i
want to achieve the selfconsistency for a particular ionic configuration
ie. i m not moving the ions, so it should achieve the selfconsistency only
once. my input file is as below.

# Crystalline La2O3 : computation of the total energy
#

##################################################################
# The following section is to be taken from each relaxed structure
rprim 1.0  0.0  0.0             # In lessons 1 and 2, these primitive vectors
      0.0  1.0  0.0             # (to be scaled by acell) were 1 0 0  0 1
0  0 0 1
      0.0  0.0  1.0             # that is, the default.
xred                   # This keyword indicate that the location of the atoms
0.000000000   0.083056210   0.155557638
0.000000000  -0.083056210  -0.155557638
0.500000000   0.083056390   0.655557907
0.500000000  -0.083056390   0.344442093
0.500000000   0.583052468  -0.155558802
0.500000000   0.416947532   0.155558802
0.000000000   0.583052689   0.344440923
0.000000000   0.416947311   0.655559077

##################################################################

  ndtset  2

#Ground state calculation
  kptopt1   1             # Automatic generation of k points, taking
                          # into account the symmetry
  tolvrs1   1.0d-18       # SCF stopping criterion
    iscf1   5             # Self-consistent calculation, using algorithm 5
#Response Function calculation : electric field perturbation and phonons

  rfphon2   1             # Activate the calculation of the atomic
dispacement perturbations
 rfatpol2   1 8           # Only these atoms will be displaced
# rfelfd3   0             # Activate the calculation of the electric field
perturbation
   rfdir2   1 1 1         # Need to consider the perturbation in the
x-direction only

    nqpt2   1
     qpt2   0.0 0.0 0.0   # This is a calculation at the Gamma point

  getwfk2   -1            # Uses as input wfs the output wfs of the dataset 1
# getddk2   -1            # Uses as input ddk wfs the output of the dataset 2

  kptopt2   2             # Automatic generation of k points,
                          # using only the time-reversal symmetry to decrease
                          # the size of the k point set.
  tolvrs2   1.0d-10
    iscf2   5             # Self-consistent calculation, using algorithm 5


#######################################################################
#Common input variables
ecut 15.0#Definition of the atom types
ntypat 1                # There are two types of atom
zatnum 31              # 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, type 1 is the
Aluminum,
                       # type 2 is the Arsenic.

#Definition of the atoms
natom 8                # There are two atoms
type 1 1 1 1 1 1 1 1   # The first is of type 1 (Al), the second is of
type 2 (As).

#Gives the number of band, explicitely (do not take the default)
nband  20              # For an insulator (if described correctly as an
insulator
                       # by DFT), there is no need to include conduction
bands
                       # in response-function calculations

ngkpt 7 7 5

tsmear 0.0015


ixc 2

#Definition of the SCF procedure
nstep  40              # Maximal number of SCF cycles
diemac 9.0             # Although this is not mandatory, it is worth to



#Definition of the unit cell
acell 8.271000  8.221374   13.961448