[Pw_forum] Number of Kpoints in nscf calculations

[Masoud Aryanpour]

Dear PWSCF users/developers,

I have used PWSCF to perform a non self-consistent calculations on a WO2
system. (Input details are attached below.)
For kpoints sampling, I use a uniform k-mesh, for example, 5x5x5 or 6x6x6.
Although each time the calculations finish without any problem, the kpoints
that are practically used are different from those specified in the input
file.

For 5x5x5=125, the output file prints 205 kpoints, and
for 6x6x6=216, the actual and applied number of kpoints equals 312.

As I understand from the manual, if the number of kpoints is not enough, it
is increased automatically by the software (please correct me if that's
wrong.)

Now my question is: how could I specify the k-meshing such that the same
mesh would be used in the calculations as in the input file?

Thanks in advance.

Masoud

=================
Masoud Aryanpour, PhD
Baker Lab
Cornell University
Ithaca, NY
EMAIL: ma526(at)cornell(dot)edu
TEL:   607-255-3681
===================
---------------------------------------------------------------- Input for
6x6x6 mesh
&control
 calculation = 'nscf'
 restart_mode= 'from_scratch'
 prefix     ='W4O8' ,
 pseudo_dir ='/home/PW/PW_pseudo' ,
 outdir     ='/home/tmp/' ,
/
&system
 ibrav  = 0 ,  celldm(1) = 0 ,
 nat  = 12 ,  ntyp = 2 ,  nbnd = 75 ,
  occupations = 'smearing'
 degauss = 0.01,   ecutwfc = 30 ,
/
&electrons
  electron_maxstep = 200
  diagonalization = 'david'
  mixing_mode = 'plain'
  conv_thr =  1.0d-8
  mixing_beta = 0.7
/
CELL_PARAMETERS cubic
   8.6808909655    0.0000000000    0.0000000000
   0.0000000000    8.6808909655    0.0000000000
   0.0000000000    0.0000000000   11.1800724827
ATOMIC_SPECIES
W  184.0   W.pw91-nsp-van.UPF
O   16.0    O.pw91-van_ak.UPF
ATOMIC_POSITIONS angstrom
W    0.0000000000     0.0000000000     0.0000000000
W    0.0000000000     0.0000000000     2.9581200000
W    2.2968650000     2.2968650000     1.4790600000
W    2.2968650000     2.2968650000     4.4371800000
O    1.3462650656     1.3462650656     0.0000000000
O    3.2474649344     3.2474649344     0.0000000000
O    3.6622465973     0.9314834027     1.4790600000
O    0.9314834027     3.6622465973     1.4790600000
O    1.3462650656     1.3462650656     2.9581200000
O    3.2474649344     3.2474649344     2.9581200000
O    3.6622465973     0.9314834027     4.4371800000
O    0.9314834027     3.6622465973     4.4371800000

K_POINTS crystal
216
  0.00000000  0.00000000  0.00000000  4.629630e-03
  0.00000000  0.00000000  0.16666667  4.629630e-03
  0.00000000  0.00000000  0.33333333  4.629630e-03
  0.00000000  0.00000000  0.50000000  4.629630e-03
  0.00000000  0.00000000  0.66666667  4.629630e-03
 ...
...
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