# NON-ADIABATIC VIBRONIC COUPLING IN 1,3,5,7-OCTATETRAENE

Please use this identifier to cite or link to this item: http://hdl.handle.net/1811/11167

Files Size Format View
1980-FC-08.jpg 121.4Kb JPEG image

 Title: NON-ADIABATIC VIBRONIC COUPLING IN 1,3,5,7-OCTATETRAENE Creators: Granville, M. F.; Kohler, Bryan E.; Schulten, K. Issue Date: 1980 Publisher: Ohio State University Abstract: trans, trans-1,3,5,7-Octatetrane in n-octane at 4.2K is an ideal polyene system in which the full implications of inversion symmetry are evident in the vibronically induced nature of the $1^{1}A_{g} - 2^{1}A_{g}$ electronic transition (1). With the aid of a high resolution two photon excitation spectrum, it is possible to quantitatively analyze the fluorescence and one photon absorption spectra in terms of the Duschinsky effect and adiabatic (Herzberg-Teller) and non-adiabatic (Born-Oppenheimer) vibronic coupling (2) between the $2^{1}A_{g}$ and $1^{1}B_{u}$ electronic states. Although the fluorescence spectrum can be explained by the usual Herzberg-Teller scheme, it is found that the one photon absorption is completely dominated by Born-Oppenheimer coupling. The form of this coupling is such that the relative signs of the normal mode displacements in the $2^{1}A_{g}$ and $1^{1}B_{u}$ states can be determined within a harmonic oscillator model. Description: $^{1}$M. F. Granville, G. R. Holtom, B. E. Kohler , R. L. Christensen, and K. L. D'Amico, J. Chem. Phys., 70, 593 (1979). $^{2}$T. Azumi and K . Matsuzaki, Photochem, Photobiol., 25, 315 (1977). Author Institution: URI: http://hdl.handle.net/1811/11167 Other Identifiers: 1980-FC-8