Nonresonant hyperhyphen;Raman and hyperhyphen;Rayleigh spectra excited at 1064 nm are reported for neat benzene and pyridine. The theory of Herzbergndash;Teller vibronic coupling in nonresonant and preresonant hyperhyphen;Raman scattering is developed. Nonresonant hyperhyphen;Raman scattering is shown to be vibronically induced by modes that efficiently couple strongly allowed onehyphen;photon and twohyphen;photon transitions. A weak and broad (55 cmminus;1) hyperhyphen;Rayleigh band was observed in benzene and attributed to collective scattering, while in pyridine, a much more intense and much narrower hyperhyphen;Rayleigh band was observed. Only thea2uvibration (ngr;11) was observed in the hyperhyphen;Raman spectrum of benzene, while several strong bands were observed in pyridine. Possible vibronichyphen;coupling pathways are discussed for these modes. In addition, the observed hyperhyphen;Raman spectrum of pyridine is compared to a recent calculation.
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