I have a DNA molecule with a known sequence ( 20 nucleotides) and I want to simulate the refractive index of the ssDNA and the refractive index of the dsDNA (when that single strand is hybridized with its complementary strand). I have read papers in which the DNA structure is simulated using Molecular Dynamic softwares and then tools like CHARMM27 or TheoDORE are used for the simulation of refractive index but I wanted to know if there are equations that one could use for such a purpose? Or perhaps if there is a simpler approach toward the problem?

I would be happy if anyone could give me more insight on the whole thing as I am not very well acquainted with the subject.

Thank you for your answers in advance