The ground state (g) and the excited state (e) dipole moments of two coumarin laser dyes, coumarin
440 and 460, were studied at room temperature in various solvents, viz., general solvents, alcohols and
liquid crystals at 298 K. In this work, we report dipole moment of laser dyes in different anisotropic (liquid
crystal) and isotropic environments for understanding the effects of environments on the molecular
dipole moment and comparing them. Ground and excited state dipole moments of coumarin dyes were
evaluated by means of solvatochromic shift method. It was observed that dipolemomentvalues of excited
states (e) were higher than the corresponding ground state values (g) in all media.
کلید واژگان :
Coumarin dyes Dipole moment Anisotropic environments Nematic liquid crystal
