[QE-users] About confirmation of ground state energy of isolated atom

[Giuseppe Mattioli]

Dear Poonam S.
As a general rule, total energies are not meaningful in the case of  
plane-wave/pseudopotentials calculations in periodic boundary  
conditions. Only total energy differences are, provided they are  
calculated in the same supercell and with the same wfc/density cutoffs.
HTH
Giuseppe

Quoting poonamsharma <poonamkaushik40 at gmail.com>:

> Dear all,
> I have one question about finding the ground state energy of an
> isolated atom.
> I considered a cubic unit cell with a vacuum of 15 angstrom. How do I know
> after computation, the ground state energy that I got is correct?
>
> Thanks and regards,
> Poonam S.
>
>
>
> -------------------------------------------------------------------------------------------------
> Poonam Sharma
> Research Scholar
> Department of Physics
> Indian Institute of Technology Bombay
> Mumbai - 400076
> India.



GIUSEPPE MATTIOLI
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