Abstract
In 1969 Oosterhoff and van der Lugt1 investigated the butadiene → cyclobutene interconversion and pointed out that a reaction would take place only if there exist such states from which a driving force can derive ; this was an elegant way of showing on theoretical grounds that a molecule electronically excited in its Franck-Condon nuclear configuration will spontaneously distort itself (relax) if the new nuclear configuration corresponds to an energy minimum which correlates with the initial state along a coordinate devoid of significant barriers. If two electronic states do not correlate with each other (regardless ΔHO) or if they do through an exceedingly high barrier or in a continuous highly endothermic way, no adiabatic interconversion would occur (interconversion does however take place diabatically at avoided surface crossings). According to and within the restrictions of the above statements a molecule, whatever in the ground or in an excited state, is entitled to move on its hypersurface. These motions (changes of internuclear angles and distances) from energy well to energy well are determined by the shape of the potential surfaces; if one were to make any prediction on chemical (or physical) transformations one should obviously have some knowledge of the potential surfaces.
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References
W.T.A.M. van der Lugt and L.J. Oosterhoff, J. Amer. Chem. Soc., 1969, 91, 6042.
J. Michl, Pure Appl. Chem., 1975, 41, 507 and references cited therein.
L. Salem, J. Amer. Chem. Soc., 1974, 96, 3486.
A. Devaquet, Pure Appl. Chem., 1975, 41, 455.
J.B. Birks, Photophysics of Aromatic Molecules, Wiley- Interscience, 1970, page 247.
D. Rondelez and S. Boué, J.C.S. Perkin II, 1976, 647.
R. Srinivasan and S. Boue, J. Amer. Chem. Soc., 1971, 93, 550.
P. Vanderlinden and S. Boue, J.C.S. Chem. Comm., 1975, 932.
This dismisses the erroneous figure based on a mass balance, which appeared in a preliminary communication8.
N. Bigwood and S. Boue, Tetrahedron Letters, 1973, 44, 4311.
S. Boue and R. Srinivasan, J. Amer. Chem. Soc., 1970, 92, 3226.
P. Bruckmann and L. Salem, J. Amer. Chem. Soc., 1976, 96, 5037.
The same scheme would hold as well if two states were formed, one of which decaying exclusively to its initial ground state and the other giving rise to the excimer. This would only change the α and β values but be of no importance to our reasoning; the lowest excimer channel contribution compatible with the numerical figures would involve ~ 3.7% of the excited molecules.
L. Salem, J. Amer. Chem. Soc., 1968, 97, 553.
D.F. Eaton, personal communication (PhD thesis, Caltech 19 72 ).
J.B. Birks, Organic Molecular Photophysics, J.B. Birks Ed., Wiley-Interscience, 1973, volume 1, page 48.
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Boué, S., Rondelez, D., Vanderlinden, P. (1977). Classical and Non-Classical Decay Paths of Electronically Excited Conjugated Dienes. In: Pullman, B., Goldblum, N. (eds) Excited States in Organic Chemistry and Biochemistry. The Jerusalem Symposia on Quantum Chemistry and Biochemistry, vol 10. Springer, Dordrecht. https://doi.org/10.1007/978-94-010-1273-7_17
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DOI: https://doi.org/10.1007/978-94-010-1273-7_17
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