[Pw_forum] symmetry operation not allowed

[karan deep]

i am trying to relax monoclinic lattice (space group no. 14) with 20 atoms
in unit cell.
pwscf is not detecting symmetry with warning

 warning: symmetry operation #  2 not allowed.   fractional translation:
       0.4988459  0.4999973 -0.5000000  in crystal coordinates
after some search i come to now

i have to specify nr1 nr2 nr3 manually  to achive
abs (ft1 - nint (ft1) ) / nr1 < 1.0d-5  for all three translations.

but i am getting very high values(10000) of nr1 and nr3  to achieve this
but nr2=100,110 works well
but high values of nr1, nr3 are not spotted.how can i get rid of this error.


Secondly my system has four symmetry operations E, C2 , i, Sh
while system is only detecting E
no warnings for i, Sh are given

any help will be greatly appreciated


Karandeep
Research Scholar
Physics Department,
IIT,  Delhi
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