Author Topic: Raman spectra calculation  (Read 109 times)

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Offline Utpal Sarkar

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Raman spectra calculation
« on: August 29, 2021, 16:27 »
Is it possible to calculate Raman spectra for different temperatures?

Offline mlee

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Re: Raman spectra calculation
« Reply #1 on: September 3, 2021, 13:41 »
It is not possible in the different temperature.
See https://docs.quantumatk.com/manual/Types/RamanSpectrum/RamanSpectrum.html

Offline Tue Gunst

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Re: Raman spectra calculation
« Reply #2 on: September 16, 2021, 17:29 »
I assume that the mechanism that you refer to is the peak position shift in Raman peaks?
The Raman peaks will shifts position due to anharmonic effects with temperature.
The best option currently would be to perform MD for a supercell to include anharmonic interaction.
In general, ensemble averaging the Raman spectra should do the job but that will of cause be computational heavy for a supercell.
A better solution would be to calculate anharmonic shifts in the phonon frequencies directly. QuantumATK currently doesn't support that but it is in the pipeline so stay tuned.