Abstract
Langevin simulations of iodine geminate recombination, which incorporate electronic surface hopping based on collisional reorientation of electronic angular momentum, suggest that deep trapping on the A and A′ state and shallow trapping on the 0Π0-u state inhibit direct recombination octo the ground state. Phase-space considerations lead to the definition of a broad transition state around 5.7 Å such that three timescales can be deduced following the rapid predissociation onto the repulsive 1Π1u surface and initial escape beyond 5.8 Å. The first ( ≈ 100 ps) is associated with the recombination process which involves deep trapping on the A and A′ states, transient shallow trapping and detrapping on the 3Π0-u state and direct recombination onto the X-state. The second ( ≈ 1 ns) is associated with detrapping of the Å state by slow escape, A to A′ and A to X crossing, while the longest timescale ( ≈ 10 ns) is detrapping of the A′ state. The latter two timescales are shown to be transport limited by virtue of the broad transition state which encompasses the region of facile curve hopping. The results are in good agreement with recent experimental results.
Original language | English |
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Pages (from-to) | 315-326 |
Number of pages | 12 |
Journal | Chemical Physics |
Volume | 96 |
Issue number | 2 |
DOIs | |
Publication status | Published - 15 Jun 1985 |
Externally published | Yes |