[Pw_forum] Convergence with respect to ecutwfc

[priyanka goud]

Dear PWSCF users,

                                     Iam calculating band structure of an
organic crystal.For the same I have performed scf calculatiions
with different cutoff.Results are as follows.








ecutwfc

* *

* *

* *

*Total Energy*

* *

* *

* *

*Difference*

 10

-923.6688



15

-945.1988

     21.53

20

-953.0299

    7.8311

25

-954.8061

    1.7762

30

-955.0794

    0.2733

35

-955.1120

    0.0326

40

-955.1538

    0.0418

45

-955.2164

    0.0626

50

-955.2699

    0.0535

55

-955.3043

    0.0344

60

-955.3239

    0.0196

65

-955.3352

    0.0113

70

-955.3416

    0.0064

75

-955.3475

    0.0059

80

-955.3571

    0.0096

85

-955.3725

   0.0154

            Kindly suggest me upto which decimal point should I see the
total energy for convergence. And here which cutoff can I take for post
processing (nscf) calculations.I am attaching the plot of ecutwfc
versesTotal energy.

 Thanks In advance .


B.Priyanka
Research Scholar,
Computational Lab,
IICT,INDIA .
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