Development of Ultraviolet-Ultraviolet Hole-burning Spectroscopy for Cold Gas Phase Ions

Féraud Géraldine

Dedonder Claude

Jouvet Christophe

Inokuchi Yoshiya

Haino Takeharu

Sekiya Ryo

Ebata Takayuki

The Journal of Physical Chemistry Letters

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.

gas phase cold ion

ion traps

conformers

uracil

electronic spectroscopy

Chemistry [ 430 ]

eng

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.

[DOI] 10.1021/jz500478w

[ISSN] 1948-7185

[NCID] AA1260018X

[DOI] https://doi.org/10.1021/jz500478w