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Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Communication: Observation of dipole-bound state and high-resolution photoelectron imaging of cold acetate anions
Dao-Ling Huang1, Guo-Zhu Zhu1, Lai-Sheng Wang1
1Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA.
Abstract:
We report the observation of a dipole-bound state and a high-resolution photoelectron imaging study of cryogenically cooled acetate anions (CH3COO(-)). Both high-resolution non-resonant and resonant photoelectron spectra via the dipole-bound state of CH3COO(-) are obtained. The binding energy of the dipole-bound state relative to the detachment threshold is determined to be 53 ± 8 cm(-1). The electron affinity of the CH3COO· neutral radical is measured accurately as 26 236 ± 8 cm(-1) (3.2528 ± 0.0010 eV) using high-resolution photoelectron imaging. This accurate electron affinity is validated by observation of autodetachment from two vibrational levels of the dipole-bound state of CH3COO(-). Excitation spectra to the dipole-bound states yield rotational profiles, allowing the rotational temperature of the trapped CH3COO(-) anions to be evaluated.
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