Bünermann O, Mudrich M, Weidemüller M, Stienkemeier F
Universität Bielefeld, Universitätsstrasse 25, D-33615 Bielefeld, Germany.
J Chem Phys. 2004 Nov 8;121(18):8880-6. doi: 10.1063/1.1805508.
Cesium oligomers are formed on helium nanodroplets which are doped with one or a few Cs atoms. The monomer absorption of the first electronic p<--s transition upon laser excitation is probed. Spectra employing laser-induced fluorescence, beam depletion, and resonant photoionization are compared. In particular, mass-resolved photoionization allows us to specifically probe excitation induced processes such as, e.g., the formation of cesium-helium exciplexes. Absorption spectra of Cs dimers and trimers are recorded in the spectral region accessible by a Ti:sapphire laser. Assignment of dimer spectra is achieved by comparison with model calculations based on ab initio potentials. Electronic absorption lines of Cs trimers are attributed to transitions in the quartet manifold.
铯低聚物在掺杂有一个或几个铯原子的氦纳米滴上形成。探测了激光激发时第一个电子p←s跃迁的单体吸收。比较了采用激光诱导荧光、光束耗尽和共振光电离的光谱。特别是，质量分辨光电离使我们能够专门探测激发诱导的过程，例如铯-氦激基复合物的形成。Cs二聚体和三聚体的吸收光谱在钛宝石激光器可及的光谱区域记录。通过与基于从头算势的模型计算进行比较，实现了二聚体光谱的归属。Cs三聚体的电子吸收线归因于四重态中的跃迁。
