Spectroscopic studies of synthesized coumarins

The ground state (µg) and excited state (µe) dipole moments of newly synthesized coumarins namely 1-(2-Methoxy-phenoxymethyl)-benzo[f]chromen-3-one (2-MPBC) and 1-(3-Methoxy-phenoxymethyl)-benzo[f]chromen-3-one (3-MPBC) were estimated at room temperature in solvents of different polarities. The excited state dipole moments were estimated using Solvatochromic shift method. It was observed that the excited state dipole moments estimated by solvatochromic shift method were larger than the ground state dipole moments, which indicates that the excited state is more polar than the ground state.