Mason Jarrett L, Topolski Josey E, Ewigleben Joshua, Iyengar Srinivasan S, Jarrold Caroline Chick
Department of Chemistry , Indiana University , 800 East Kirkwood Avenue , Bloomington , Indiana 47405 , United States.
J Phys Chem Lett. 2019 Jan 17;10(2):144-149. doi: 10.1021/acs.jpclett.8b03253. Epub 2018 Dec 26.
The photoelectron spectra of SmO obtained over a range of photon energies exhibit anomalous changes in relative excited-state band intensities. Specifically, the excited-state transition intensities increase relative to the transition to the neutral ground state with decreasing photon energy, the opposite of what is expected from threshold effects. This phenomenon was previously observed in studies on several Sm-rich homo- and heterolanthanide oxides collected with two different harmonic outputs of a Nd:YAG (2.330 and 3.495 eV) [ J. Chem. Phys. 2017, 146, 194310]. We relate these anomalous intensities to populations of ground and excited anionic and neutrals states through the inspection of time-dependent perturbation theory within the adiabatic and sudden limits and for the first time show that transition intensities in photoelectron spectroscopy have a deep significance in gauging participation from excited states. We believe our results will have significance in the study of other electron-rich systems that have especially high density of accessible spin states.
在一系列光子能量范围内获得的SmO光电子能谱显示出相对激发态能带强度的异常变化。具体而言，随着光子能量降低，相对于中性基态的跃迁，激发态跃迁强度增加，这与阈值效应所预期的情况相反。此前在对几种富含Sm的同核和异核镧系氧化物的研究中观察到了这种现象，这些研究使用了Nd:YAG的两种不同谐波输出（2.330和3.495 eV）[《化学物理杂志》2017年，第146卷，第194310页]。我们通过在绝热和突然极限内检查含时微扰理论，将这些异常强度与基态和激发态阴离子及中性态的布居联系起来，并首次表明光电子能谱中的跃迁强度在衡量激发态的参与程度方面具有深刻意义。我们相信我们的结果将对其他具有特别高可及自旋态密度的富电子系统的研究具有重要意义。
