Velocity Map Imaging Spectroscopy of the Dipole-Bound State of CH2CN–: Implications for the Diffuse Interstellar Bands
| Autor: | Stephen Gibson, Timothy W. Schmidt, Zachariah D. Levey, Benjamin A. Laws |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Chemistry
Binding energy General Chemistry 010402 general chemistry 01 natural sciences Biochemistry Molecular physics Catalysis 0104 chemical sciences Ion Dipole Colloid and Surface Chemistry X-ray photoelectron spectroscopy Electron affinity 0103 physical sciences Bound state Spectroscopy Absorption (electromagnetic radiation) 010303 astronomy & astrophysics |
| Zdroj: | Journal of the American Chemical Society. 143:18684-18692 |
| ISSN: | 1520-5126 0002-7863 |
| Popis: | Weakly bound anionic systems present a new domain for negative ion spectroscopy. Here we report on a multifaceted study of the CH2CN- dipole-bound state, employing high-resolution photoelectron spectroscopy from 130 different wavelengths, velocity-map imaging at threshold, and laser scanning photodetachment experiments. This uncovers a wide variety of different vibrational and rotational autodetaching resonances. By examination of both sides of the problem, absorption from the anion to the dipole-bound state and vibrational/rotational autodetachment to the neutral, a complete model of the dipole-bound chemistry is formed. Precise values for the electron affinity EA = 12468.9(1) cm-1, dipole binding energy DBE = 40.2(3) cm-1, and anion inversion splitting ω5 = 115.9(2) cm-1 are obtained. This model is then employed to study possible astronomical implications, revealing good agreement between the K = 1 ← 0 CH2CN- dipole transition and the λ8040 diffuse interstellar band. |
| Databáze: | OpenAIRE |
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