Wagner J Philipp, McDonald David C, Colley Jason E, Franke Peter R, Duncan Michael A
Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, USA.
J Chem Phys. 2021 Oct 7;155(13):134302. doi: 10.1063/5.0065477.
The protonated HCl dimer and trimer complexes were prepared by pulsed discharges in supersonic expansions of helium or argon doped with HCl and hydrogen. The ions were mass selected in a reflectron time-of-flight spectrometer and investigated with photodissociation spectroscopy in the IR and near-IR regions. Anharmonic vibrational frequencies were computed with VPT2 at the MP2/cc-pVTZ level of theory. The Cl-H stretching fundamentals and overtones were measured in addition to stretch-torsion combinations. VPT2 theory at this level confirms the proton-bound structure of the dimer complex and provides a reasonably good description of the anharmonic vibrations in this system. The trimer has a HCl-HClH-ClH structure in which a central chloronium ion is solvated by two HCl molecules via hydrogen bonding. VPT2 reproduces anharmonic frequencies for this system, including several combinations involving core ion Cl-H stretches, but fails to describe the relative band intensities.
通过在掺杂有HCl和氢气的氦气或氩气的超声速膨胀中进行脉冲放电来制备质子化的HCl二聚体和三聚体配合物。离子在反射式飞行时间光谱仪中进行质量选择，并在红外和近红外区域用光解离光谱进行研究。在MP2/cc-pVTZ理论水平下用VPT2计算非谐振动频率。除了伸缩-扭转组合外，还测量了Cl-H伸缩基频和泛音。该水平的VPT2理论证实了二聚体配合物的质子键合结构，并对该系统中的非谐振动提供了相当好的描述。三聚体具有HCl-HClH-ClH结构，其中中心氯鎓离子通过氢键被两个HCl分子溶剂化。VPT2再现了该系统的非谐频率，包括涉及核心离子Cl-H伸缩的几种组合，但未能描述相对谱带强度。
