Table of Contents
Laser Chemistry
Volume 19, Issue 1-4, Pages 101-103

Coherent Motion of Low Frequency Vibrations in Ultrafast Excited State Proton Transfer

Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Berlin D-12489, Germany

Received 11 April 1997

Copyright © 1999 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Photoexcitation of internal proton transfer in the tinuvin molecule causes the excitation of some low frequency vibrational modes which oscillate with high amplitudes in a coherent manner over 700 fs. Such effect is observed for the first time applying two color pump/probe measurement with 25 fs pulses. Based on resonance Raman spectra a normal coordinate analysis of the modes is performed. It is shown that the nuclear movement given by the normal vibration of one of the modes serves to open up a barrierfree proton transfer path.