Abstract
The question of excitation selectivity in unimolecular reactions induced by infrared multiple photon excitation (IRMPE) was probed by using the isotopically labeled molecule CH3SCCSCD3. The relatively rigid SCCS group was inserted in order to serve as a block to fast intramolecular energy exchange between the CH3 and CD3 moieties. Irradiation by a CO2 laser pulse could initially selectively excite either one. Probing was done in real time at low pressures (∼10-4 torr) by vacuum-UV laser single-photon ionization. At all irradiation wavelengths, equal amounts of CH3 and CD3 radicals were formed. Thus, fast intramolecular energy exchange on the time scale of the IRMPE process is directly demonstrated.
Original language | English |
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Pages (from-to) | 5162-5167 |
Number of pages | 6 |
Journal | Journal of Physical Chemistry |
Volume | 88 |
Issue number | 22 |
DOIs | |
State | Published - 1984 |