Units of NLO Calculations

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jerkov
Posts: 28
Joined: Tue Nov 26, 2019 6:02 pm

Units of NLO Calculations

Post by jerkov » Sat Jun 13, 2020 12:50 am

Hi all,

I'm confused about the units of various values in my NLO anaddb output file.

What are the units of Raman susceptibility? From the accompanying paper (10.1103/PhysRevB.71.125107) eqn. 28 suggests it would be something like bohr^(3/2), but that seems to contradict the Raman polarizability's usual units.
Next, what is the oscillator strength unit (eqn 42)? It says in a.u., 1 a.u.=253.2638413 m3/s2, but if it's units are the square of the mode polarity, shouldn't it be coolumb^2*bohr^2?

Cheers,
J

jerkov
Posts: 28
Joined: Tue Nov 26, 2019 6:02 pm

Re: Units of NLO Calculations

Post by jerkov » Mon Nov 23, 2020 3:59 pm

Hi,

I'd like to repeat this question, as it's something with which 'm still struggling!

Best,
J

BagLuc
Posts: 1
Joined: Thu Jul 16, 2015 2:40 pm

Re: Units of NLO Calculations

Post by BagLuc » Fri Dec 04, 2020 8:57 am

Hi,

To my knowledge, we are rarely interested in absolute values of Raman intensities, because Raman spectra absolute values depends on experimental parameters that are rarely measured (like the exposure light beam time). So one usually compares relative intensities, and there is no problem of units.

Are you interested in absolute values for some reason?

Best,
Lucas

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