Computational study of electronic-vibrational spectrum of rotamers of 2-(2'-hydroxyphenyl)benzoxazole

UV-vis absorption spectrum of internally hydrogen-bonded enol structures 2-(2'-hydroxyphenyl)benzoxazole is calculated for the transitions to first excited state using Franck-Condon approximation and harmonic model vibrations. It shown that structure with hydrogen bond OH...O shifted larger energy by about 0.13 eV compared most stable OH...N. The largest intensity vibronic electronic demonstrates high-frequency vibrations involving deformation mode oxazole ring, stretching both aromatic rings, linking benzoxazole phenyl moieties.