The absorption and emission spectra of fluorescent molecule namely 6-Methyl-3-[1-(4, 5-dicarbomethoxy-1,
2, 3-triazoloacetyl)] coumarin (6MDTC) has been recorded at room temperature in solvents of different
polarities. The exited state (μe) dipole moment was estimated from Lippert’s, Bakhshiev’s and Kawski-
Chamma-Viallet’s equations using the variation of Stoke’s shift with the solvents of different polarities
using dielectric constant and refractive index. The geometry of the molecule was fully optimized and the
ground state dipole moment (μg) was also calculated theoretically by Gaussian 03 software using B3LYP/6-
31g* level of theory. The μg and μe were calculated by solvatochromic shift method and μe was also
determined in combination with μg. It was observed that μe was greater than that of the μg, indicating a
substantial redistribution of the π-electron densities in a more polar excited state for this coumarin. Further,
the changes in dipole moment (Δμ) was calculated both from solvatochromic shift method and on the basis
of microscopic empirical solvent polarity ( ) and the values are compared