Abstract
We report high level ab initio and infrared multiphoton dissociation (IRMPD) studies of protonated and sodiated asparagine, a chiral molecule, in the NH and OH stretching region using a newly completed laboratory IRMPD spectrometer. These two systems were previously investigated in the low frequency region of 520–1820 cm−1 at the FELIX facility (Heaton et al., 2009). The new laboratory IRMPD instrument features ion production by nano-electrospray ionization (ESI), using either a standard atmospheric implementation or a novel subambient pressure ionization with nano-electrospray design, a quadrupole mass filter, a 3D quadrupole ion trap for storage and irradiation of the selected ions and a reflectron time-of-flight mass spectrometer in an orthogonal configuration. In addition, the new instrument contains a second ion guide/ion trap arm for further coupling with a helium nanodroplet isolation spectrometer. A desktop, continuous wave, IR OPO laser system is used to excite the ions from ca. 3200 to 4000 cm−1. Furthermore, high level theoretical calculations and comparison of the experimental and theoretical IR spectra are used to establish the relative energy ordering of the conformers of protonated and sodiated asparagine. The new instrument will be put to use to study non-covalent interactions between chiral molecules across different cluster sizes and compositions.
Accepted Version (
Free)
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call