Atomic scattering factor for compounds

[freeone]

Hi there,

I am trying to calculate diffraction efficiencies of a lattice with the coupled wave theory. As material parameters the programm I got needs the atomic scattering factor f1 and f2. (see http://henke.lbl.gov/optical_constants/asf.html for elements)
I understood this seems to correlate to the values δ and β in the complex index of refraction for atoms. This seems not to be true for compounds. As there is of course a index of refraction defined for compounds (http://henke.lbl.gov/optical_constants/getdb2.html).

Is there an equivalent number for the optical properties for composite materials?

Thanks,
freeone

 

[eljose79]

Hello freeone,

Thank you for your question. The atomic scattering factor, or ASF, is a fundamental parameter used in the calculation of diffraction efficiencies. It is a measure of how strongly atoms scatter light and is related to the complex index of refraction for individual atoms. However, as you mentioned, this does not directly apply to compounds or composite materials.

In order to calculate the diffraction efficiencies for composite materials, you will need to consider the individual ASFs for each element present in the material. This can be done by using the mass fractions of each element and their corresponding atomic scattering factors. The overall diffraction efficiency is then calculated by taking into account the interactions between the different elements in the composite material.

Alternatively, you can also use the complex index of refraction for the compound, which takes into account the interactions between the different elements. This can be found in databases such as the one you mentioned (http://henke.lbl.gov/optical_constants/getdb2.html).

I hope this helps clarify the calculation process for diffraction efficiencies in composite materials. Please let me know if you have any further questions.