Dipartimento di Chimica Ugo Schiff-Università di Firenze, via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy.
Phys Chem Chem Phys. 2013 Jul 21;15(27):11268-74. doi: 10.1039/c3cp50191d. Epub 2013 Jun 3.
The binding energies of the neutral and positively charged anisole dimer have been determined in molecular beam-laser spectroscopy experiments. This is the first report on the direct experimental determination of the binding energy for an aromatic cluster in π stacked configuration. The anisole dimer is formed by two anisole molecules superimposed in a planar arrangement and it has been proposed as a model system in which the π-stacking interaction, among other intermolecular forces, plays a relevant role. Its binding energy has been determined thanks to both velocity mapping ion/electron imaging experiments and previous spectroscopic information. The binding energy amounts to 3926(250) cm(-1) in the ground state and 4144(250) cm(-1) in the S2 (first spectroscopically accessible) electronic excited state; its value for the positively charged dimer ion increases to 6147(250) cm(-1). These values are quite higher with respect to the results of previous DFT calculations.
中性和带电茴香二聚体的结合能已在分子束-激光光谱实验中确定。这是首次直接实验确定π堆叠构型中芳香族团簇的结合能。茴香二聚体由两个茴香分子以平面排列叠加而成，它被提议作为一个模型体系，其中π-堆积相互作用（among other intermolecular forces）起着重要作用。其结合能通过速度映射离子/电子成像实验和先前的光谱信息得以确定。在基态下，其结合能为 3926(250)cm(-1)，在 S2（第一个可光谱探测到的）电子激发态下为 4144(250)cm(-1)；在带正电的二聚体离子中，其值增加到 6147(250)cm(-1)。这些值相对于先前 DFT 计算的结果要高得多。
