title: Slow excited state phototautomerization in 3-hydroxyisoquinoline.
abstract: In the present work we report the spectral and photophysical properties of 3-hydroxyisoquinoline in various protic/aprotic solvents. Our steady state and time resolved fluorescence data indicates that in the monomer form of 3HIQ phototautomerization can take place in the excited state through excited state intramolecular proton, while as per earlier suggestions phototautomerization in 3HIQ occurs in dimer or complex (in the presence of acetic acid) form. Moreover, we find rather slow tautomerization (occurring on the nanosecond scale). It is found that proton transfer occurs both in the ground as well as excited states and is controlled by the polarity of the solvent.
authors.affiliation: Photophysics Laboratory, Department of Physics, DSB Campus, Kumaun University, Nainital 263002, Uttarakhand, India.
authors.forename: Neeraj Kumar
authors.initials: NK
authors.lastname: Joshi
authors.forename: Priyanka
authors.initials: P
authors.lastname: Arora
authors.forename: Sanjay
authors.initials: S
authors.lastname: Pant
authors.forename: Hem Chandra
authors.initials: HC
authors.lastname: Joshi