Chemical probing spectroscopy of H3+ above the barrier to linearity

Abstract

We have performed chemical probing spectroscopy of H3+ ions trapped in a cryogenic 22-pole ion trap. The ions were buffer-gas cooled to 55K by collisions with helium and argon. Excitation to states above the barrier to linearity was achieved by a Ti:Sa laser operated between 11300 and 13300 cm-1. Subsequent collisions of the excited H3+ ions with argon lead to the formation of ArH+ ions that were detected by a quadrupole mass spectrometer with high sensitivity. We report the observation of 17 previously unobserved transitions to states above the barrier to linearity. Comparison to theoretical calculations suggests that the transition strengths of some of these lines are more than five orders of magnitude smaller than those of the fundamental band, which renders them - to the best of our knowledge - the weakest H3+ transitions observed to date.

22 pages, 5 figures, submitted to JCP

References in corpus (4)

• H3+ in Diffuse Interstellar Clouds: a Tracer for the Cosmic-Ray Ionization Rate
• Photodetachment of cold OH- in a multipole ion trap
• Evaporation of buffer gas-thermalized anions out of a multipole rf ion trap
• Spectroscopy and dissociative recombination of the lowest rotational states of H3+

Cited by in corpus (10)

• Radiofrequency multipole traps: Tools for spectroscopy and dynamics of cold molecular ions
• Internal state thermometry of cold trapped molecular anions
• How can a 22-pole ion trap exhibit 10 local minima in the effective potential?
• The Low-Temperature Nuclear Spin Equilibrium of H3+ in Collisions with H2
• Terahertz-visible two-photon rotational spectroscopy of cold OD-
• Visible line intensities of the triatomic hydrogen ion from experiment and theory
• ExoMol line lists -- L: High-resolution line lists of H${}_3^{+}$, H${}_2$D${}^{+}$, D${}_2$H${}^{+}$ and D${}_3^{+}$
• High accuracy calculations of the rotation-vibration spectrum of H${}_3^{+}$
• Finite temperature quantum statistics of H${}_3^{+}$ molecular ion
• Spectroscopy and dissociative recombination of the lowest rotational states of H3+