University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands.
J Am Chem Soc. 2010 Oct 13;132(40):14086-91. doi: 10.1021/ja1034655.
Infrared spectroscopy provides a means to determine the intrinsic geometrical structures of molecules. Here we present a novel spectroscopic method that uses superfluid helium nanodroplets to record IR spectra of cold molecular ions, in this particular case aniline cations. The method is based on the detection of ions that are ejected from the helium droplets following vibrational excitation of these ions. We find that spectra can be recorded with a high sensitivity and that they exhibit only a small matrix shift. The widths of the individual transitions depend on the excited vibrational level and are thought to be related to the interaction of the ion with the surrounding helium solvent shells.
红外光谱提供了一种确定分子固有几何结构的手段。在这里，我们提出了一种新的光谱方法，该方法使用超流氦纳米液滴记录冷分子离子的红外光谱，在这种特殊情况下是苯胺阳离子。该方法基于检测从氦液滴中射出的离子，这些离子是在这些离子的振动激发后被检测到的。我们发现，可以以高灵敏度记录光谱，并且它们仅显示出较小的基质位移。各个跃迁的宽度取决于激发的振动能级，并且被认为与离子与周围氦溶剂壳的相互作用有关。
