Fluorescence excitation spectra, lifetimes, and quenching of S/sub 2/(B /sup 3/S/sub u//sup -/) in the wavelength region 280--315 nm
Fluorescence lifetimes have been determined for S/sub 2/ vapor excited to the B /sup 3/S/sub u//sup -/ state at wavelengths in the range 280--315 nm, with a spectral resolution of approx.0.5 cm/sup -1/. For states with v'< or =8, excitation in the bandhead region leads to fluorescence lifetimes of approx.30--45 ns. In addition, low-intensity peaks with much longer lifetimes are observed throughout the absorption spectrum. The decreased intensity and increased lifetime are attributed to perturbations by the B'' /sup 3/r/sub u/ state. For the v' = 9 state, lifetimes generally decrease as the excitation wavelength moves away from the bandhead and at some wavelengths a double exponential decay was observed. Although the v' = 10 state is known to predissociate, weak fluorescence peaks with very short lifetimes (<3 ns) were observed. The addition of Ar as a quenching gas leads to complex fluorescence decay curves with two or three components for both v' = 3 and v' = 9 states. Lifetimes and quenching rate constants obtained in this work agree with those measured previously in this laboratory using a broad-band excitation source.
- Research Organization:
- Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973
- OSTI ID:
- 6439611
- Journal Information:
- J. Chem. Phys.; (United States), Vol. 74:9
- Country of Publication:
- United States
- Language:
- English
Similar Records
Intermolecular vibrations and relaxation dynamics in complexes of OH {ital A}{sup 2}{Sigma}{sup +} ({ital v}{prime}=0,1) with N{sub 2}
Lifetimes and collisional quenching cross sections of single rotational states in bromine
Related Subjects
SULFUR
EMISSION SPECTRA
FLUORESCENCE
NEAR ULTRAVIOLET RADIATION
ABSORPTION SPECTRA
DIMERS
ELECTRONIC STRUCTURE
LIFETIME
ELECTROMAGNETIC RADIATION
ELEMENTS
LUMINESCENCE
NONMETALS
RADIATIONS
SPECTRA
ULTRAVIOLET RADIATION
640302* - Atomic
Molecular & Chemical Physics- Atomic & Molecular Properties & Theory