Related Experiment Video
Updated: Jun 26, 2026

Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown
Published on: February 14, 2014
Gas-phase spectroscopy of the 2 3Sigma(-)-X 3Sigma- electronic transition of CCS
Masakazu Nakajima1, Timothy W Schmidt, Akira Miyoshi
1School of Chemistry, University of Sydney, New South Wales 2006, Australia.
Abstract:
Gas-phase laser excitation spectra of the jet-cooled CCS radical were observed for the 2 (3)Sigma(-)-X (3)Sigma(-) electronic transition in a discharge of a gas mixture containing acetylene and H(2)S in Ar. The observed excitation spectra show complicated rotational structures, consisting of a much larger number of rotational lines than those expected for this size of linear molecule. The excited vibronic levels emit fluorescence, the lifetime of which is much longer than that estimated theoretically, indicating that the upper levels are strongly mixed with many "dark" background levels. Dispersed fluorescence spectra from single vibrational levels of the 2 (3)Sigma(-) state show long progressions of the C-S stretching mode, enabling observations of many vibrational levels in the ground electronic state.
Related Concept Videos
UV–Vis Spectroscopy: Molecular Electronic Transitions
2D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)
Molecular Orbital Theory II
¹³C NMR: ¹H–¹³C Decoupling
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
Atomic Spectroscopy: Absorption, Emission, and Fluorescence
¹H NMR: Complex Splitting
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
