Related Experiment Video
Updated: Apr 5, 2026

Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Vibrational State-Selective Resonant Two-Photon Photoelectron Spectroscopy of AuS(-) via a Spin-Forbidden Excited
Hong-Tao Liu1,2, Dao-Ling Huang1, Yuan Liu3
1†Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States.
Abstract:
Vibrational state-selective resonant two-photon photoelectron spectra have been obtained via a triplet intermediate state ((3)Σ(-)) of AuS(-) near its detachment threshold using high-resolution photoelectron imaging of cryogenically cooled AuS(-) anions. Four vibrational levels of the (3)Σ(-) excited state are observed to be below the detachment threshold. Resonant two-photon absorptions through these levels yield vibrational state-selective photoelectron spectra to the (2)Σ final state of neutral AuS with broad and drastically different Franck-Condon distributions, reflecting the symmetries of the vibrational wave functions of the (3)Σ(-) intermediate state. The (3)Σ(-) excited state is spin-forbidden from the (1)Σ(+) ground state of AuS(-) and is accessed due to strong relativistic effects. The nature of the (3)Σ(-) excited state is confirmed by angular distributions of the photoelectron images and quantum calculations.
Related Concept Videos
Molecular Spectroscopy: Absorption and Emission
UV–Vis Spectroscopy: Molecular Electronic Transitions
Deactivation Processes: Jablonski Diagram
Atomic Nuclei: Nuclear Spin State Overview
Atomic Spectroscopy: Absorption, Emission, and Fluorescence
Atomic Emission Spectroscopy: Overview

