Convert absorption coefficient units between Hitran, Lifbase

[SK1.618]

Hi,

I have some modelling code that uses data from Hitran 2012 (https://www.cfa.harvard.edu/hitran/Download/HITRAN2012.pdf). I want to use some data from Lifbase but unfortunately the absorption coefficient units do not match.

Lifbase units are given in m3 J-1 s-2 whereas Hitran units are given as cm-1 / (molecule cm-2).

Some simple calculations arrives at the following conversion between the two:

[Hitran units] = ( M_r / (100 * N_A) ) * [Lifbase units]

where M_r is the molecular mass of the species and N_A is Avogadro's constant.

For some reason this does not seem to be correct. The absorption coefficients are out by a few orders of magnitude. Is my conversion correct?

Thanks in advance!

 

[AndyW]

Hello,

Thank you for your post. It seems like you have made a good effort in trying to convert the units between Hitran and Lifbase. However, it is important to note that the absorption coefficient is a measure of the intensity of absorption, and is not dependent on the units used for its calculation. Therefore, the conversion between the units should not affect the magnitude of the absorption coefficient.

I would suggest double-checking your calculations and also making sure that you are using the correct values for molecular mass and Avogadro's constant. If the absorption coefficients are still significantly different, it is possible that there may be other factors at play, such as different experimental conditions or data sources. In that case, it may be helpful to consult with experts in the field or refer to other literature for comparison.

I hope this helps and good luck with your research!