Structure, energetics and reaction dynamics vibrational spectra of gaseous ions

我们在下一个授权期内研究气相离子化学的总体目标将是进一步了解在气相离子经常表现出的不寻常的成键环境中发现的分子间和分子内相互作用的性质。这些目标将主要使用我们在滑铁卢实验室建造的四个新的实验设备来实现。其中包括三台配置在单聚焦和双聚焦磁扇形质谱计周围的高压质谱仪(HPM)和一台配备高压离子-分子簇源的傅立叶变换离子回旋共振(FTICR)质谱仪。此外，在自由电子激光(FEL)设备CLIO与巴黎南奥赛大学FTICR光谱仪的合作下，我们将获得新型团簇离子的红外光解离光谱，从而给出上述这些新型成键环境的振动特征。所有进行的实验研究通常都得到高水平电子结构计算的补充，这些计算有助于获得结构和能量方面的见解。我们的注意力最近转向了从具有生物学意义的分子中衍生出的离子的化学。对质子化氨基酸与小的碱性分子底物之间相互作用的能量学的氨基酸的初步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变为两性离子实体。

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.