Report on the outcomes of a Short-Term Scientific Mission

Action number: CA21101

Applicant name: Liliia Uvarova

Details of the STSM

Title: Study of overtone transitions of HCNH+ in the spectral region around 6800 cm-1 using 22 pole ion trap.

Start and end date: 10/07/2023 to 04/08/2023

Description of the work carried out during the STSM

The 22-pole radiofrequency ion trap apparatus at the host institution (Max Planck Institute for Extraterrestrial Physics (MPE), Garching, Germany) was used to measure overtone spectrum of HCO+.

In order to get the goal of STSM the following steps were done:

  1. The optical system with the triple-pass cell was made to improve the detection sensitivity of the laser induced reaction (LIR) by increasing the total optical path of laser light that travels through the 22 pole trap. The DFB laser with central wavelength 1647 nm was used for that reason.
  2. Predictions of HCO+ transitions of 0000 → 2000 (ν1ν2l ν3, where ν1, ν2, and ν3 denote the numbers of vibrational quanta in the relevant vibrational modes, l is the quantum number associated with the vibrational angular momentum of the doubly degenerate ν2 bending vibration) band was done by using the vibrational constants from [Neese, 2013]. More information about the nomenclature and corrections of vibrational constants can be found in paper [Neese, 2013] and [Neese, 2014]. HCO+ ions were created in SIS. The overtone spectrum of HCO+ was studied using endothermic reaction: HCO+ + CO2→ HCO2+ + CO. This reaction can take place in case HCO+ ions can get additional energy from the laser irradiation. The transitions P(1)-P(4) were measured with good agreement with our predictions.
  3. During the study we studied the quenching of the vibrationally excited state of HCO+ ions with different gasses, such as He, N2, H2 and Ne.

Neese C. F., Kreynin P.S. and T. Oka, J. Phys. Chem. A, 117, 39, 9899–9907, 2013.

Neese C. F., Kreynin P.S. and T. Oka, J. Phys. Chem. A, 118, 5358−5358, 2014. (correction)

Description of the STSM main achievements and planned follow-up activities


  1. We managed to measure the overtone transitions of HCO+;
  2. We measured the quenching rate of the v1 = 2 excited state of HCO+ with
    different gases.

The next steps:

  1. Preparations for the measurement of HOC+ spectrum are now underway.
  2. Preparations for the measurement of HCNH+ spectrum will be done in the near future.

The results of measurements of the spectrum of overtone transitions are expected to be published in impacted journal. Another outcome of the STSM is the improved collaboration between MPE and Prague laboratories.

Working group 5) Confined Systems in Astrochemistry: Gas- and Condensed-Phase Spectroscopy and Reactivity

Objectives/deliverables supported by the work:

5.6.3 Thermochemical and kinetic database for gas-phase chemistry in the interstellar medium (the quenching rate of the excited state of HCO+ with different gases and the lifetime of this excited state was obtained. The measured overtone spectrum will be utilized in a following study of recombination of HCO+ ions with electrons using CRDS technique)

5.7.3 Spectroscopic characterization of astrochemical molecules and set-up of a database/WG2 (we measured the overtone spectrum of astrochemically important HCO+ ion)

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