Calculation of energy band gap or optical obsorption from UV-Vis spectrum is possible. Is there any relation between these parameters with refractive index for glass samples?
My glass samples are estimated to have refractive index above 2. The thickness of the glass samples would be around 1 mm.
It is possible to approximately calculate the refractive index dispersion as long as you have the absorption data from a sufficiently large range and also know all relevant phase shifts by using a Kramers-Kronig relation:
Because of the Kramers–Kronig relations, the wavelength dependence of the real part of the refractive index is related to the material absorption, described by the imaginary part of the refractive index (also called the extinction coefficient). In particular, for non-magnetic materials (μ = μ0), the susceptibility that appears in the Kramers–Kronig relations is the electric susceptibility: http://en.wikipedia.org/wiki/Dispersion_(optics)
In addition to knowing the absorption spectrum, you'll need to build an interferometer to also measure phases, because Kramers Kronig relations work for complex numbers.
http://en.wikipedia.org/wiki/Kramers–Kronig_relations
It is possible to approximately calculate the refractive index dispersion as long as you have the absorption data from a sufficiently large range and also know all relevant phase shifts by using a Kramers-Kronig relation:
Because of the Kramers–Kronig relations, the wavelength dependence of the real part of the refractive index is related to the material absorption, described by the imaginary part of the refractive index (also called the extinction coefficient). In particular, for non-magnetic materials (μ = μ0), the susceptibility that appears in the Kramers–Kronig relations is the electric susceptibility: http://en.wikipedia.org/wiki/Dispersion_(optics)
In addition to knowing the absorption spectrum, you'll need to build an interferometer to also measure phases, because Kramers Kronig relations work for complex numbers.
http://en.wikipedia.org/wiki/Kramers–Kronig_relations
If absorbtion is very small and can be ignored, then you can use this method: http://pubs.acs.org.virtual.anu.edu.au/doi/pdf/10.1021/ed079p619
Absolutely agree with A. S. Solntsev. Just to add that if the absorption is small enough and the studied sample has some transmittance different from zero you can measure transmittance and reflectance spectra and calculate simultaneously refractive index and exctinction coefficient using thickness as known parameter. See the attached paper
And another thing. If you have some information about the dispersion curves of n and k, you can use an appropriate dispersion models for them and determine the models parameters using non-linear curve fitting of reflectance spectra. Hope this help
This link may help
http://www.instanano.com/characterization/theoretical/uv-vis-spectroscopy-band-gap-calculation/
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