On May 13, 2021, Park, Woojin; Lee, Seunghoon; Huix-rotllant, Miquel; Filatov, Michael; Choi, Cheol ho published an article.Category: pyrimidines The title of the article was Impact of the Dynamic Electron Correlation on the Unusually Long Excited-State Lifetime of Thymine. And the article contained the following:
Non-radiative relaxation of the photoexcited thymine in the gas phase shows an unusually long excited-state lifetime, and, over the years, a number of models, i.e., S1-trapping, S2-trapping, and S1&S2-trapping, have been put forward to explain its mechanism. Here, we investigate this mechanism using non-adiabatic mol. dynamics (NAMD) simulations in connection with the recently developed mixed-reference spin-flip time-dependent d. functional theory (MRSF-TDDFT) method. We show that the previously predicted S2-trapping model was due to an artifact caused by an insufficient account of the dynamic electron correlation. The current work supports the S1-trapping mechanism with two lifetimes, τ1 = 30 ± 1 fs and τ2 = 6.1 ± 0.035 ps, quant. consistent with the recent time-resolved experiments Upon excitation to the S2 (ππ*) state, thymine undergoes an ultrafast (ca. 30 fs) S2→S1 internal conversion and resides around the min. on the S1 (nOπ*) surface, slowly decaying to the ground state (ca. 6.1 ps). While the S2→S1 internal conversion is mediated by fast bond length alternation distortion, the subsequent S1→S0 occurs through several conical intersections, involving a slow puckering motion. The experimental process involved the reaction of 5-Methylpyrimidine-2,4(1H,3H)-dione(cas: 65-71-4).Category: pyrimidines
The Article related to impact dynamic electron correlation long excited state lifetime thymine, General Physical Chemistry: General Theories and other aspects.Category: pyrimidines
Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia