Author Topic: Energy per atom of metal  (Read 2723 times)

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Offline ams_nanolab

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Energy per atom of metal
« on: July 10, 2017, 07:49 »
How to calculate energy/atom of metals as Li or Na (bulk) ?

Offline Petr Khomyakov

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Re: Energy per atom of metal
« Reply #1 on: July 10, 2017, 08:54 »
You can calculate the total energy using the analysis object 'Total energy' and divide it by the number of atoms to get the total energy per atom.

Offline ams_nanolab

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Re: Energy per atom of metal
« Reply #2 on: July 10, 2017, 09:04 »
In the case of Na for example, I add the BCC Na structure from database (i.e. Na(beta)), use 16x16x16 k-points to simulate bulk and as the cell contains just one atom, that should be the total energy/atom (Em) of BCC Na?

Also how I get the cohesive energy of Na? Simulate a single na atom and subtract from previous energy/atom(Em)?
« Last Edit: July 10, 2017, 09:06 by ams_nanolab »

Offline Petr Khomyakov

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Re: Energy per atom of metal
« Reply #3 on: July 10, 2017, 11:51 »
In the case of Na for example, I add the BCC Na structure from database (i.e. Na(beta)), use 16x16x16 k-points to simulate bulk and as the cell contains just one atom, that should be the total energy/atom (Em) of BCC Na?

Yes. Otherwise, the total energy of an ideal crystal is infinite because it is comprised of an infinite number of atoms.

Also how I get the cohesive energy of Na? Simulate a single na atom and subtract from previous energy/atom(Em)?

I guess so, see https://en.wiktionary.org/wiki/cohesive_energy.