Radiative cooling of polyyne anions: C4H- and C6H-

Zhu, Boxing, Bull, James N. ORCID: https://orcid.org/0000-0003-0953-1716, Navarro Navarrete, Jose E., Schmidt-May, Alice Frederike, Cederquist, Henrik, Schmidt, Henning T., Zettergren, Henning and Stockett, Mark H. (2022) Radiative cooling of polyyne anions: C4H- and C6H-. The Journal of Chemical Physics, 157 (17). ISSN 0021-9606

[thumbnail of 1273806_2_merged_1664798780]
Preview
PDF (1273806_2_merged_1664798780) - Accepted Version
Download (2MB) | Preview

Abstract

The time-dependent photodetachment action spectra of the linear hydrocarbon anions C4H- and C6H- are investigated using the cryogenic electrostatic ion storage ring DESIREE. Radiative cooling characteristics of the ions on the millisecond to second timescale are probed by monitoring changes in the spectra as the ions cool by spontaneous infrared (IR) emission. A simple harmonic cascade (SHC) model is used to model the cooling processes. The cooling rates, extracted using Non-negative Matrix Factorization (NMF), are fit with 1/e lifetimes of 19 {plus minus} 2 s and 3.0 {plus minus} 0.2 s for C4H- and C6H-, respectively. For C4H-, the adiabatic detachment energy is determined from the cold ions' photodetachment spectra to be 3.45 {plus minus} 0.02 eV. The photodetachment spectrum and the ultraslow radiative cooling dynamics interpreted in the present work provide important data for understanding the thermal cooling properties of linear hydrocarbon anions and for refining the formation and destruction processes of these anions in astrochemical models.

Item Type: Article
Faculty \ School: Faculty of Science > School of Chemistry
Related URLs:
Depositing User: LivePure Connector
Date Deposited: 10 Oct 2022 13:31
Last Modified: 04 Nov 2022 14:30
URI: https://ueaeprints.uea.ac.uk/id/eprint/88929
DOI: 10.1063/5.0111144

Actions (login required)

View Item View Item