IR Spectroscopy of Fullerene Ions in a Cryogenic Quadrupole Trap
| Autor: | Juraj Jašík, Jana Roithová, Dieter Gerlich, Dmitry Strelnikov |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Physics
Buffer gas chemistry.chemical_element Infrared spectroscopy Astronomy and Astrophysics 010402 general chemistry 01 natural sciences Spectral line 0104 chemical sciences Ion chemistry Space and Planetary Science 0103 physical sciences Atom Quadrupole Spectroscopy and Catalysis Ion trap Atomic physics 010303 astronomy & astrophysics Helium |
| Zdroj: | The Astrophysical Journal, 864, 1, pp. 1-9 The Astrophysical Journal, 864, 1-9 |
| ISSN: | 0004-637X |
| Popis: | This paper reports gas-phase IR spectra of (n = 1–3) ions in the range from 1100 to 1600 cm−1. The spectra were recorded with a temperature-variable radio frequency ion trap instrument. The experiments work with mass-selected ions confined in a linear wire quadrupole, where they form helium-tagged complexes following exposure to low-temperature (as low as 2.3 K) and high-density helium buffer gas. All measured lines are homogeneously broadened owing to a strong coupling between the vibrational states of the fullerene cage. The short lifetimes of picoseconds or below rule out measurements of high-resolution IR spectra. Reproducible sidebands with distances between 5 and 20 cm−1 enrich the spectra. Tentative explanations are based on nonlinear and symmetry-breaking interactions or may be due to the influence of the attached He atom. Comparison of the spectrum with that of reveals shifts up to 6 cm−1, while the IR spectra of and are very similar. With the harmonic potential of the trap the ions are squeezed into the rather narrow laser beam, increasing the sensitivity and simplifying the determination of absolute photoabsorption cross sections. Disregarding shifts of several cm−1, the gas-phase results for and are in agreement with previous matrix results and with theoretical predictions. The astrophysical relevance of our results is briefly mentioned. |
| Databáze: | OpenAIRE |
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