Table of Contents
Laser Chemistry
Volume 19 (1999), Issue 1-4, Pages 275-277

Vibrational Energy Relaxation in the (d, d) Excited State Of Nickel Octaethylporphyrin

Institute for Molecular Science, the Graduate University for Advanced Studies, Myodaiji, Okazaki 444, Japan

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.


The formation of a hot photoproduct of nickel octaethylporphyrin (NiOEP) upon ππ* excitation and its subsequent vibrational energy relaxation were monitored by picosecond time-resolved resonance Raman spectroscopy. Resonance Raman bands due to the photoproduct instantaneously appeared upon the photoexcitation. Their intensities decayed with a time constant of 330±20ps, which indicates electronic relaxation form the (d, d) excited state (B1g) to the ground state (B1g). Anti-Stokes ν4 band of the hot (d, d) excited state of NiOEP appeared immediately after the excitation and decayed with time constants of 11±2 and 330±40 ps. In contrast, the rise of anti- Stokes ν7 intensity was not instantaneous but delayed by 2.6±0.5 ps, which suggests that IVR has not been completed in a subpicosecond time regime.