Structure, energetics and reaction dynamics vibrational spectra of gaseous ions

在下一个资助期内，我们在气相离子化学方面研究的总体目标将是进一步推进对在气相离子经常显示的不寻常的键合环境中发现的分子间和分子内相互作用性质的理解。这些目标将主要使用我们在滑铁卢实验室建造的四个新型实验装置来解决。这包括三台高压质谱仪（HPMS），配置在单聚焦和双聚焦磁扇形质谱仪周围，以及一台傅立叶变换离子回旋共振（FTICR）光谱仪，配备高压离子分子簇源。此外，在一项涉及自由电子激光（FEL）设备CLIO的合作中，我们将获得新型簇离子的红外光解光谱，从而给出上述新型键合环境的振动特征。CLIO与巴黎大学苏德奥赛分校的FTICR光谱仪连接。所有进行的实验研究通常都辅以高水平的电子结构计算，这有助于获得结构和能量的洞察力。最近，我们的注意力转向了从具有生物学意义的分子中提取离子的化学性质。质子化氨基酸与小分子底物之间相互作用的能量学的初步HPMS研究表明，这些相互作用可以相对容易地导致氨基酸部分从中性转化为两性离子实体。

The general objectives of our research in gas phase ion chemistry over the next grant period will be to further advance the understanding of the nature of inter- and intra-molecular interactions found in the unusual bonding environments frequently displayed by gas phase ions. These objectives will be addressed primarily using the four novel experimental apparatus that we have constructed in our laboratory at Waterloo. These constitute three high pressure mass spectrometers (HPMS) configured around both single and double focusing magnetic sector mass spectrometers and a Fourier Transform Ion Cyclotron Resonance (FTICR) spectrometer equipped with a high pressure ion-molecule cluster source. In addition, in a collaboration involving the Free Electron Laser (FEL) facility, CLIO, interfaced with a FTICR spectrometer at the University de Paris Sud-Orsay, we will obtain infra-red photodissociation spectra of novel cluster ions thus giving vibrational signatures of these novel bonding environments noted above. All of the experimental studies carried out are routinely complemented by high level electronic structure calculations which aid in gaining structural and energetic insight. Our attention has recently turned towards the chemistry of ions derived from molecules of biological significance. Initial HPMS studies of amino acids of the energetics of interaction between protonated amino acids and small, basic molecular substrates have revealed the relative ease with which these interactions can lead to the transformation of the amino acid moiety from a neutral to a zwitterionic entity.