Picosecond Kinetic and Vibrationally Resolved Spectroscopic Studies of Intramolecular Excited Hydrogen Atom Transfer.

Laser studies on intramolecular hydrogen atom (H) transfer in organics have led to an important insight into the mechanism of ultrafast H transfer reactions. Two types of molecules have been studied. The first type is exemplified by the compound 9- hydroxyphenalenone for which the H transfer is manifested as tunneling splittings in the vibronic spectroscopy of compounds in this class. The second type is exemplified by the molecules 2- (2-hydroxyphenyl)benzothiazole and 3-hydroxyflavone, for which the H transfer can be studied by ultrafast emission spectroscopy. This paper discusses recent research on both types of compounds, emphasizing results from the authors and their coworkers, at AT&T Bell Laboratories and the University of Minnesota.