The role of the intersection space in the photochemistry of tricyclo[3.3.0.02,6]octa-3,7-diene

Journal of Physical Chemistry A

Volumn 111, Issue 15, 2007, Pages 2830-2838

  Frutos, Luis Manuel ^a   Sancho, Unai ^a   Garavelli, Marco ^b   Olivucci, Massimo ^c,d   Castaño, Obis ^a  

^a UNIVERSITY OF ALCALÁ   (Spain)

^b UNIVERSITY OF BOLOGNA   (Italy)

^c UNIVERSITY OF SIENA   (Italy)

^d BOWLING GREEN STATE UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

INTERSECTION SPACE; PERICYCLIC REACTIONS; PHOTOCHEMICAL BEHAVIOR; SPACE DIAGRAMS;

MOLECULAR STRUCTURE; PHOTOCHEMICAL REACTIONS; REACTION KINETICS; SILICON;

OLEFINS;

EID: 34247626320     PISSN: 10895639     EISSN: None     Source Type: Journal    
DOI: 10.1021/jp067590t     Document Type: Article

References (30)

1. (a) For a recent review, see: Migani, A. and Olivucci, M. In Conical Intersections. Electronic Structure, Dynamics and Spectroscopy, Domcke, W., Yarkony, D. R., Koppel, H. Eds.; World Scientific: Singapore, 2004.
2. (b) Olivucci, M. and Sinicropi, A. In Computational Photochemistry; Olivucci, M. Ed.; Elsevier: Amsterdam, 2005; Vol. 16.
3. (c) Garavelli, M. Theor. Chem. Acc. 2006, 116, 87-105.
4. See for example: (a) Salem, L. Electrons in Chemical Reactions: First Principles; Wiley: New York, 1982, pp 149-151.
5. (b) Kiessinger M, Michl J. Excited States and Photochemistry of Organic Molecules; VCH Publishers: New York, 1994.
6. See, for example (a) Migani, A.; Robb, M. A.; Olivucci, M. J. Am. Chem. Soc. 2003, 125, 2804-2808.
7. (b) Frutos, L. M.; Sancho, U.; Castaño, O. Org. Lett. 2004, 6, 1229-1231.
8. (c) Cembran, A.; Bernardi, F.; Garavelli, M.; Gagliardi, L.; Orlandi, G. J. Am. Chem. Soc. 2004, 126, 3234-3243.
9. Meinwald, J.; Tsuruta, T. J. Am. Chem. Soc. 1970, 92, 2579.
10. (a) Gleiter, R.; Kobayashi, T. Helv. Chim. Acta 1971, 54, 1081.
11. (b) Bischof, P.; Gleiter, R.; Haider, R. Angew. Chem., Int. Ed. Engl. 1977, 16, 110.
12. (c) Kanda, K.; Koremoro, T.; Imamura, A. Tetrahedron 1986, 42, 4169.
13. A total of 8e, 8MO has been chosen for the active space, corresponding to 4e, 4MO for the two double bonds (n Orbitals) and 4e, 4MO (two first HOMOs and two first LUMOs) for the central cyclobutane ring (a orbitals).
14. 2 respectively. The corresponding eigenvectors, which were all orthogonal to the gradient, give the direction of energy decrease within a second order approximation for the PES around the FC geometry on Si.
15. These five directions provide a five-dimensional subspace of energy decreases in a second order approximation, while the orthogonal force (i.e., minus energy gradient) vector provides a first-order decrease in the energy. Therefore, any linear combination of these six vectors gives a six-order dimensional subspace of potential energy decrease within first- and second-order expansion of the PES.
16. 8).
17. 20 MEPs in So were computed for every CI, taking as initial direction to follow the corresponding 20 equally spaced vectors (0.1π radians) belonging to the plane defined by the gradient difference (GD) and derivative coupling (DC) vectors of each CI.
18. Unless the experimentally observed photoproducts (SBV and COT in an approximate ratio of 1:2) are involved, the formation of structural isomers of COT which rapidly isomerize to COT is not excluded, even at temperatures as low as -60 °C. See ref 4.
19. The BR intermediate on Si has biradical character, but with a contribution from a tetraradical form.
20. (a) Cheng, A. K.; Anet, F. A. L.; Mioduski, J.; Meinwald, J. J. Am. Chem. Soc. 1974, 96, 2887.
21. (b) Castano, O.; Frutos, L.-M.; Palmeiro, R.; Notario, R.; Andres, J.-L.; Gomperts, R.; Blancafort, L.; Robb, M. A. Angew. Chem., Int. Ed. 2000, 39, 2095.
22. (c) Jiao, H. J.; Nagelkerke, R.; Kurtz, H. A.; Williams, R. V.; Borden, W. T.; Schleyer, P. V. J. Am. Chem. Soc. 1997, 119, 5921.
23. 15.
24. By performing MEP computations in the intersection subspace (with a standard conical intersection optimization algorithm as implemented in the Gaussian suite of programs. See ref 18), CIM has been located from CI1 and CI2.
25. By a domain of a stationary CI (i.e., vanishing gradient in the intersection space) we mean a continuous subspace of CIs in which the stationary CI is included. This implies that, for every CI point of this subspace, a MEP exists in the intersection space that connects that point to the stationary CI.
26. (a) Garavelli, M.; Bernardi, F.; Moliner, V.; Olivucci, M. Angew. Chem., Int. Ed. 2001, 40, 1466.
27. (b) Garavelli, M.; Bernardi, F.; Cembran, A.; Castaño, O.; Frutos, L. M.; Merchán, M.; Olivucci, M. J. Am. Chem. Soc. 2002, 124, 13770.
28. Calculations were made with: Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.; Robb, M. A.; Cheeseman, J. R.; Zakrzewski, V. G.; Montgomery, J. A., Jr.; Stratman, R. E.; Burant, J. C.; Dapprich, Millam, S. J. M.; Daniels, A. D.; Kudin, K. N.; Strain, M. C.; Farkas, O.; Tomasi, J.; Barone, V.; Cossi, M.; Cammi, R.; Menucci, B.; Pomelli, C.; Adamo, C.; Clifford, S.; Ochterski, J.; Petersson, G. A.; Ayala, P. Y.; Cui, Q.; Morokuma, K.; Malick, D. K.; Rabuck, A; Raghavachari, D. K.; Foresman, J. B.; Cioslowski, J.; Ortiz, J. V.; Stefanov, B. B.; Liu, G.; Liashenko, A.; Piskorz, P.; Komaromi, I.; Gomperts, R.; Martin, R. L.; Fox, D. J.; Keith, T.; Al-Laham, M. A.; Peng, C. Y.; Nanayakkara, A.; Gonzalez, C.; Challacombe, M.; Gill, P. M. W.; Johnson, B. G.; Chen, W.; Wong, M. W.; Andres, J. L.; Gonzalez, C.; Head-Gordon, M.; Replogle, E. S.; Pople, J. A. Gaussian 98, Revsion A.7; Gaussian, Inc.: Pittsburgh PA, 1998.
29. Calculation were made with: Andersson, K.; Barysz, M.; Bernhardsson, A.; Blomberg, M. R. A.; Carissan, Y.; Cooper, D. L.; Fülscher, M. P.; Gagliardi, L.; de Graaf, C.; Hess, B. A.; Hagberg, D.; Karlström, G.; Lindh, R.; Malmqvist, Nakajima, P.-Å.; T.; Neogrády, P.; Olsen, J.; Raab, J.; Roos, B. O.; Ryde, U.; Schimmelpfennig, B.; Schütz, M.; Seijo, L.; Serrano-Andrés, L.; Siegbahn, P. E. M.; Stålling, J.; Thorsteinsson, T.; Veryazov, V.; Widmark, P.-O. MOLCAS, version 6; Lund University: Lund, Sweden, 2004.
30. Algorithm taken from: Palmeiro, R. Ph.D. Dissertation, University of Alcala, Spain, 2004.