Probing the intramolecular hydrogen bond of 2-(2-hydroxyphenyl)benzotriazoles in polar environment: a photophysical study of UV absorber efficiency

The photophysical and structural characterization of a series of 2-(2-hydroxyphenyl)benzotriazoles (HBzTs) is carried out to determine the effective strength of their chelate-type hydrogen bond. The findings provide insight into photostabilization dynamics due to strong intramolecular hydrogen bond (IMHB) which could be applied to design new UV absorbers with optimum strength.