Ab Initio Multiple Spawning Photochemical Dynamics of DMABN Using GPUs

Curchod, Basile F.E.; Sisto, Aaron; Martínez, Todd J.

Abstract

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).

Citation

Curchod, B. F., Sisto, A., & Martínez, T. J. (2017). Ab Initio Multiple Spawning Photochemical Dynamics of DMABN Using GPUs. The Journal of Physical Chemistry A, 121(1), 265-276. https://doi.org/10.1021/acs.jpca.6b09962

• Journal Article Type: Article
• Acceptance Date: Oct 2, 2016
• Online Publication Date: Dec 15, 2016
• Publication Date: Jan 12, 2017
• Deposit Date: Nov 6, 2017
• Publicly Available Date: Dec 15, 2017
• Journal: The Journal of Physical Chemistry A
• Print ISSN: 1089-5639
• Electronic ISSN: 1520-5215
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 121
• Issue: 1
• Pages: 265-276
• DOI: https://doi.org/10.1021/acs.jpca.6b09962
• Public URL: https://durham-repository.worktribe.com/output/1344704