In a fcc or bcc lattice of Fe atoms (or Cobalt or Aluminum, or potentially any element) , for a supercell of 16 Fe atoms with periodic boundary condition, how do you estimate the total ground state energy of the system? The total energy is defined to include the kinetic energy of the electrons and potential energy due to the Columbic interactions among electron-electron, electron-nuclei, and nuclei-nuclei. The kinetic energy of the nuclei is not included under the Born-Oppenheimer approximation. What experimental values can be cited or theoretical calculations done to give a rough estimate of the total energy on the order of magnitude? Ab initio is one way, but I want to find out other ways to confirm with the ab initio results.(adsbygoogle = window.adsbygoogle || []).push({});

I tried to use the first a few ionization energies of Fe to estimate the binding energy due to one atom and then multiply by 16 to get the total energy of the system. But of course, this calculation doesn't include the potential energy due to atom-atom interaction. Also, I was told that things in solids dramatically change and the single-atom approximation doesn't have much truth to it. So I'm wondering if there is a better way to make an estimate of the total energy of the system.

Thanks in advance

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# Energy of a Fe supercell?

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