Spectrum Calculations

Queries about input and output files, running specific calculations, etc.


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jess_white
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Spectrum Calculations

#1 Post by jess_white » Tue Nov 19, 2024 6:47 am

Hi,

I was wondering if VASP supports spectrum calculations and if so what TAGS should be added into the INCAR? I did some research and it looks like it is LOPTICS? Is that correct?

Many thanks,
Jess


pedro_melo
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Re: Spectrum Calculations

#2 Post by pedro_melo » Tue Nov 19, 2024 9:54 am

Dear Jess,

What system are you studying and what kind of interactions do you want to consider? This greatly influences the type of calculation you should perform.

Kind regards,
Pedro


jess_white
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Re: Spectrum Calculations

#3 Post by jess_white » Wed Nov 20, 2024 12:41 am

Hi Pedro,

It is looking at different minerals and looking at their IR spec. However what other spec properties can Vasp look at?

Many thanks,
Jess


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Re: Spectrum Calculations

#4 Post by jess_white » Wed Nov 20, 2024 4:42 am

Also reflectivity :)


pedro_melo
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Re: Spectrum Calculations

#5 Post by pedro_melo » Wed Nov 20, 2024 4:42 pm

Dear Jess,

Both infrared absorption and reflectivity can be computed from the dynamical dielectric function, \(\epsilon(\omega)\). In the page Category:Dielectric properties you can find details on all possible calculations that VASP can perform for \(\epsilon(\omega)\), the approximations involved, and links to the respective pages.

I suggest that you start by exploring our wiki and tutorials and try to understand which calculation type is most appropriate for what you want to study. From there the specific INCAR tags should become evident.

Kind regards,
Pedro


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