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Multidimensional characterization of the conical intersection seam in the normal mode space† †Electronic supplementary information (ESI) available: SEVI (slow electron velocity map imaging) spectra via selected S1 vibrations, (two- or three-component) deconvolution of TKER distributions of two thioanisole isotopomers. See DOI: 10.1039/d0sc02045a

ABSTRACT: Multidimensional conical intersection seam has been characterized by utilizing the dynamic resonances in the nonadiabatic transition probability experimentally observed in the predissociation of thioanisole isotopomers. Multidimensional conical intersection seam has been characterized by utilizing the dynamic resonances in the nonadiabatic transition probability experimentally observed in the predissociation of thioanisole isotopomers. The nonadiabatic bifurcation behavior of the reactive flux into either the Herzberg type-I (electronic) or type-II (vibrational) predissociation pathway is found to be strongly dependent on the quantum nature of the S1/S2 vibronic eigenstate, providing the essential information about structure and dynamic character of the conical intersection seam projected onto the normal mode space. By modifying the nature of the normal mode space through partial or full H/D substitution of the molecule, multiple aspects of the conical intersection seam could be characterized from different viewpoints set by the adjusted normal mode space. Theoretical calculations of potential energy curves along selected normal mode displacements support the experiment.

SUBMITTER: Lee H

PROVIDER: S-EPMC7504900 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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