Szabla Rafał, Šponer Jiří, Góra Robert W
†Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, 61265 Brno, Czech Republic.
‡CEITEC-Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, CZ-62500 Brno, Czech Republic.
J Phys Chem Lett. 2015 Apr 16;6(8):1467-71. doi: 10.1021/acs.jpclett.5b00261. Epub 2015 Apr 6.
The fates of photochemically formed πσ* states are one of the central issues in photobiology due to their significant contribution to the photostability of biological matter, formation of hydrated electrons, and the phenomenon of photoacidity. Nevertheless, our understanding of the underlying molecular mechanisms in aqueous solution is still incomplete. In this paper, we report on the results of nonadiabatic photodynamics simulations of microhydrated 2-aminooxazole molecule employing algebraic diagrammatic construction to the second order. Our results indicate that electron-driven proton transfer along H2O wires induces the formation of πσ*/S0 state crossing and provides an effective deactivation channel. Because we recently have identified a similar channel for 4-aminoimidazole-5-carbonitrile [Szabla, R.; Phys. Chem. Chem. Phys. 2014, 16, 17617-17626 ], we conclude this mechanism may be quite common to all heterocyclic compounds with low-lying πσ* states.
光化学形成的πσ态的命运是光生物学的核心问题之一，因为它们对生物物质的光稳定性、水合电子的形成以及光酸性现象有重大贡献。然而，我们对水溶液中潜在分子机制的理解仍然不完整。在本文中，我们报告了采用二阶代数图示构建法对微水合2-氨基恶唑分子进行非绝热光动力学模拟的结果。我们的结果表明，沿着H2O线的电子驱动质子转移诱导了πσ/S0态交叉的形成，并提供了一个有效的失活通道。由于我们最近为4-氨基咪唑-5-甲腈确定了一个类似的通道[Szabla, R.; Phys. Chem. Chem. Phys. 2014, 16, 17617 - 17626]，我们得出结论，这种机制可能对所有具有低πσ*态的杂环化合物都很常见。
