[QE-users] ZERO-POINT ENERGY IN QUANTUM ESPRESSO

[Chiara Cignarella]

Dear Ashley,

You can use the frequencies obtained by phonon calculations to compute the zero-point energy using the formula (you can find that in textbooks on the quantum harmonic oscillator part - for example Ashcroft pag. 451- ), i.e. doing the sum  \sum_i 1/2 * \omega_i * hbar (divided by appropriate normalization factor for your sum)

Note that the computed phonons do not contain themselves the ZPM contributions!


Hope this is useful.


Best regards,

Chiara Cignarella
-------------------------------------
Post-doc researcher
University of Bremen

> On 12 Aug 2025, at 09:51, Barsha Pal <barsha.pal at aus.ac.in> wrote:
> 
> Hello, 
> I have a small doubt regarding whether or not zero-point energy calculation is possible in Quantum Espresso, I want to perform that for a 2D material and adsorption cases. The property that I aim, includes the zero-point energy correction for the 2D surface and the 2D surface with adsorbed atoms. AI tells me that it is possible to do by phonon calculation. If indeed this is possible, can you guide me towards a short example? 
> 
> Thank you.
> Ashley Cooper
> Phd
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