Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic.
Charles University, Faculty of Mathematics and Physics, Ke Karlovu 3, 121 16 Prague 2, Czech Republic.
J Phys Chem B. 2022 Jan 13;126(1):229-238. doi: 10.1021/acs.jpcb.1c08172. Epub 2021 Dec 22.
We report valence band photoelectron spectroscopy measurements of gas-phase and liquid-phase benzene as well as those of benzene dissolved in liquid ammonia, complemented by electronic structure calculations. The origins of the sizable gas-to-liquid-phase shifts in electron binding energies deduced from the benzene valence band spectral features are quantitatively characterized in terms of the Born-Haber solvation model. This model also allows to rationalize the observation of almost identical shifts in liquid ammonia and benzene despite the fact that the former solvent is polar while the latter is not. For neutral solutes like benzene, it is the electronic polarization response determined by the high frequency dielectric constant of the solvent, which is practically the same in the two liquids, that primarily determines the observed gas-to-liquid shifts.
我们报告了气相和液相苯以及苯在液氨中的价带光电子能谱测量结果，同时还进行了电子结构计算。从苯价带光谱特征推断出的电子结合能在气相和液相之间的大的相移的起源，通过 Born-Haber 溶剂化模型进行了定量描述。尽管前者溶剂是极性的而后者不是，但该模型还允许解释在液氨和苯中观察到几乎相同的位移。对于像苯这样的中性溶质，主要是由溶剂的高频介电常数决定的电子极化响应，在这两种液体中实际上是相同的，决定了观察到的气相到液相的位移。
