Where \(u_{\max}\)is maximum wavenumber in solvent and \(u_{max,}\) is
maximum wavenumber in gaseous state and\(f\left(n\right),\ f\left(\varepsilon\right)\) are solvent factors
depending on refractive index and electronic permittivity, respectively.
The solute-solvent interaction can be effectively studied by
solvatochromatic effect which is defined as the shift in spectrum
(Stokes shifts) that usually depends upon relationship between polarity
of solvent and emission spectrum of photoactive specie
[77,78].