[Pw_forum] ecut vs energy

[Amin Torabi]

Dear experts!

Could you please have a look at my input file, attached to this email.

My main problem is that I expect the total energy to converge at lower
ecutwfc energy. ( or I am expecting too much?)

ecut    energy
25     -38.36026321
30     -38.44145201
35     -38.49537648
40     -38.53312799
45     -38.55904483
50     -38.57650475
55     -38.58840904
60     -38.59670631
65     -38.60253103
70     -38.60653038
75     -38.60918176
80     -38.61090436
85     -38.61200805
90     -38.61269007
95     -38.61308582
100    -38.61329742



Notes:

1. Do I have to be at the minimum structure to check for convergence of ecut
vs energy, or I can check the convergency from a non-optimized structure?

2. I used USPP for one of my atoms and NCPP for the other atom, and set
ecutrho = 10*ecutwfc...



Many thanks in advance!
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