Theory and Control of Photo-excited Polyatomic Reactions



An important process in nature is the photo-excitation of a polyatomic molecule, which initially is at the local surface temperature of the earth. Before excitation, the internal energy distribution of the molecule is the equilibrium Boltzmann distribution. The fate of this distribution after photo-excitation of the molecule from a ground electronic state (S0) to an excited electronic state (S1) has been rather ignored. The nature of the nascent vibrational distribution after photo-excitation is the topic of this paper. Our work in recent years has shown that the photo-excitation process can lead to a significant change in the vibrational population of the molecule in the excited state1,2. Within the Condon approximation, if the excitation wavelength is to the blue of the transition frequency from the ground vibrational state of the ground electronic state, to the ground vibrational state in the excited electronic state (ω00), then the molecule is usually heated. Interestingly, at the ω00 transition frequency or somewhat to the red of it one may expect under rather general conditions2 that the nascent distribution will be cooled. The cooling effect is predicted to be generic for polyatomic molecules2 and is caused by the lowering of vibrational frequencies in the excited electronic surface (in general this lowering reflects the weakening of the chemical bonds due to the electronic excitation).


Ground Electronic State Excited Electronic State Polyatomic Molecule Photoinduced Electron Transfer Ground Vibrational State 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Gershinsky G., and Pollak E., 1997, J. Chem. Phys. 107: 812.ADSCrossRefGoogle Scholar
  2. 2.
    Wadi H., and Pollak E., 1999, J. Chem. Phys. 110: 11890.ADSCrossRefGoogle Scholar
  3. Yan Y.J., and Mukamel S., J. Chem. Phys. 85: 5908.Google Scholar
  4. 4.
    Swiderek P., Hohlneicher G., Maluendes S. A., and Dupuis M., 1993, J. Chem. Phys. 98: 974.ADSCrossRefGoogle Scholar
  5. 5.
    He Y., and Pollak E., 2001, J. Phys. Chem., 2001, 105: 10961.CrossRefGoogle Scholar
  6. 6.
    Beddard G.S, Fleming G.R., Gijzeman O.L.J., and Porter G., 1974, Proc. R. Soc. Lond. A 340: 519.ADSCrossRefGoogle Scholar
  7. 7.
    Beddard G.S., Formosinho S.J., and Porter G., 1973, Chem. Phys. Lett. 22: 235.ADSCrossRefGoogle Scholar
  8. He Y., and Pollak E., preprint, submitted to J. Chem. Phys.1.Google Scholar
  9. 9.
    Talkner P., Pollak E., and Berezhkovskii A. M., 1998, Chem. Phys. 235: 131.CrossRefADSGoogle Scholar
  10. 10.
    Balk M.W., and Fleming G.R., 1986, J. Phys. Chem. 90: 3975.CrossRefGoogle Scholar
  11. 11.
    Schroeder J., Schwarzer D., Troe J., and F. Voß, 1990, J. Chem. Phys. 93: 2393.ADSCrossRefGoogle Scholar
  12. 12.
    Warmuth Ch., Milota F., Kauffmann H.F., Wadi H. and Pollak E.,2000, J. Chem. Phys. 112: 3938.ADSCrossRefGoogle Scholar
  13. 13.
    Pollak E., and He Y., 2001, J. Phys. Chem. B, 105: 6500.CrossRefGoogle Scholar
  14. 14.
    Pollak E., and Plimak L., 2001, J. Chem. Phys., 115: 1867.ADSCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2002

Authors and Affiliations

  1. 1.Chemical Physics DepartmentWeizmann Institute of ScienceRehovotIsrael

Personalised recommendations