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Tracking intramolecular energy redistribution dynamics in aryl halides: the effect of halide mass.

ABSTRACT: Selective excitation of C-H, C-C, CX¹ and CX² stretching vibrational modes in an orderly manner, detection of intramolecular energy redistribution and vibrational coupling in the electronic ground state of aryl halides are performed by time- and frequency-resolved Coherent Anti-Stokes Raman Scattering (CARS) spectroscopy. Intramolecular energy flow from parent modes to daughter modes is observed in the experiment. According to the experimental results, it is found that the up-hill vibrational energy flow from lower frequency modes to higher frequency ones is counterintuitive and energy redistribution efficiencies are controlled by the mass of the halide. The selectivity and directionality of energy flow are also discussed in view of vibrational symmetry.

SUBMITTER: Liu X

PROVIDER: S-EPMC9085276 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Tracking intramolecular energy redistribution dynamics in aryl halides: the effect of halide mass.

Liu Xiaosong X Song Yunfei Y Zhang Wei W Zhu Gangbei G Lv Zhe Z Liu Weilong W Yang Yanqiang Y

RSC advances 20180823 52

Selective excitation of C-H, C-C, CX1 and CX2 stretching vibrational modes in an orderly manner, detection of intramolecular energy redistribution and vibrational coupling in the electronic ground state of aryl halides are performed by time- and frequency-resolved Coherent Anti-Stokes Raman Scattering (CARS) spectroscopy. Intramolecular energy flow from parent modes to daughter modes is observed in the experiment. According to the experimental results, it is found that the ...[more]

PMID: 35547304

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