Solvatochromic and Quantum-Mechanical Characterization of Methyl Red

ABSTRACT

Quantum-mechanical characterization for methyl red was performed using density function theory. The dipole moment and polarizability in the ground state of methyl red were theoretically calculated. The contribution of intermolecular interactions to spectral shifts in solution and the limits in which the excited states’ dipole moment vary in the neutral form were established by a solvatochromic study. The solvatochromism of the acid and alkaline forms of methyl red was experimentally measured and compared with calculated spectra.

KEYWORDS:

• Methyl red
• quantum-mechanical calculation
• solvatochromic study
• ultraviolet–visible spectrophotometry