An experimental and theoretical investigation of the photophysics of 1-hydroxy-2-naphthoic acid

Photophysical and photochemical properties of 1-hydroxy-2-naphtotic acid (1,2-HNA) are investigated experimentally by steady state and time domain fluorescence measurements and theoretically by Hartee-Fock, configuration interaction at the single excitation level, density functional theoretic and semiempirical methods. The differences in the photophysical behavior of 1,2-HNA and 3,2-HNA can be attributed to the differences in the hydrogen bonding strength, geometry, and changes in the excited-state pKa values.