Ab Initio Multiple Spawning Photochemical Dynamics of DMABN Using GPUs
Autor: | Basile F. E. Curchod, Todd J. Martínez, Aaron Sisto |
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Rok vydání: | 2016 |
Předmět: |
010304 chemical physics
Wave packet Dynamics (mechanics) Torsion (mechanics) 010402 general chemistry 01 natural sciences 0104 chemical sciences Photoexcitation Benzonitrile chemistry.chemical_compound chemistry Ab initio multiple spawning Excited state 0103 physical sciences Density functional theory Physical and Theoretical Chemistry Atomic physics |
Zdroj: | Journal of physical chemistry A, 2017, Vol.121(1), pp.265-276 [Peer Reviewed Journal] Journal of Physical Chemistry A |
ISSN: | 1520-5215 |
Popis: | The ultrafast decay dynamics of 4-(N,N-dimethylamino)benzonitrile (DMABN) following photoexcitation was studied with the ab initio multiple spawning (AIMS) method, combined with GPU-accelerated linear-response time-dependent density functional theory (LR-TDDFT). We validate the LR-TDDFT method for this case and then present a detailed analysis of the first ≈200 fs of DMABN excited-state dynamics. Almost complete nonadiabatic population transfer from S2 (the initially populated bright state) to S1 takes place in less than 50 fs, without significant torsion of the dimethylamino (DMA) group. Significant torsion of the DMA group is only observed after the nuclear wavepacket reaches S1 and acquires locally excited electronic character. Our results show that torsion of the DMA group is not prerequisite for nonadiabatic transitions in DMABN, although such motion is indeed relevant on the lowest excited state (S1). |
Databáze: | OpenAIRE |
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