Röder A, Humeniuk A, Giegerich J, Fischer I, Poisson L, Mitrić R
Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany.
Phys Chem Chem Phys. 2017 May 17;19(19):12365-12374. doi: 10.1039/c7cp01437f.
We present a joint experimental and computational study of the nonradiative deactivation of the benzyl radical, CH, after UV excitation. Femtosecond time-resolved photoelectron imaging was applied to investigate the photodynamics of the radical. The experiments were accompanied by excited state dynamics simulations using surface hopping. Benzyl has been excited at 265 nm into the D-band (ππ*) and the dynamics was probed using probe wavelengths of 398 nm or 798 nm. At a probe wavelength of 398 nm a single time constant of around 70-80 fs was observed. When the dynamics was probed at 798 nm, a second time constant τ = 1.5 ps was visible, which can be attributed to further non-radiative deactivation to the lower-lying D/D states.
我们展示了一项关于紫外激发后苄基自由基（CH）非辐射失活的联合实验和计算研究。飞秒时间分辨光电子成像被用于研究该自由基的光动力学。实验同时进行了使用表面跳跃的激发态动力学模拟。苄基在265 nm处被激发到D带（ππ*），并使用398 nm或798 nm的探测波长来探测动力学。在398 nm的探测波长下，观察到一个约70 - 80 fs的单一时间常数。当在798 nm探测动力学时，第二个时间常数τ = 1.5 ps可见，这可归因于向较低能级的D/D态的进一步非辐射失活。
