Development of Ultraviolet-Ultraviolet Hole-burning Spectroscopy for Cold Gas Phase Ions
JPhysChemLett_2014_5_1236.pdf 3.79 MB
gas phase cold ion
A new ultraviolet-ultraviolet hole-burning (UV-UV HB) spectroscopic scheme has been developed for cold gas phase ions in a quadrupole-ion-trap (QIT) connected with a time-of-flight (TOF) mass spectrometer. In this method, a pump UV laser generates a population hole for the ions trapped in the cold QIT and a second UV laser (probe) monitors the population hole for the ions extracted to the field free region of the TOF mass spectrometer. Here, the neutral fragments generated by the UV dissociation of the ions with the second laser are detected. This UV-UV HB spectroscopy was applied to protonated dibenzylamine and to protonated uracil. Protonated uracil exhibits two strong electronic transitions; one has a band origin at 31760 cm-1 and the other at 39000 cm-1. From the UV-UV HB measurement and quantum chemical calculations, the lower energy transition is assigned to the enol-keto tautomer and the higher energy one to the enol-enol tautomer.
This study was supported in part by the France-Japan Collaboration Program (SAKURA) France, the Japan Society for Promotion of Science and the ANR Research Grant (ESPEM- ANR2010BLANC040501).
The Journal of Physical Chemistry Letters
American Chemical Society
Copyright (c) 2014 American Chemical Society
This document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Physical Chemistry Letters, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/jz500478w.