The refractive index (R2) is the inverse of T2 (the spin-spin relation time). The spin-spin relaxation time can be obtained from NMR.

This relation between R2 and T2 forms the basic relation in the calibration of human lenses where the pixel intensity (I) is related to spin-spin relation time (T2) as follows:

I=Io e ^-R2.TE

TE is the Eco Time and is calibrated by MRI.

Please read spin-sin relation time as spin-spin relaxation time. Typographical error is regretted.

Thank you! I understand quite alright!

I would imagine that in systems where refractive index is utilized to measure the density or viscosity of a material there would be a direct correlation between T1 and T2 measurements obtained on the same materials. We have also found that PLS regression of NMR spectral variability, example would be in heavy vacuum gas oils in petroleum industry, correlates well to refractive index which is typically used to determine aromaticity (% carbon aromatic content ). The NMR experiment readily observes the relative amount of either aromatic protons or aromatic carbons in the sample that can then be correlated to refractive index.

Thank you Dr. Edwards. Kindly refer me to your articles in which the points you have rightly mentioned are published! I really love to have them!

You might also like to search for work by Pope et al., who measured the correlation between relaxation time and refractive index in eye lens.

Thank you, Professor Wellard