Fluorescence lifetimes and Zeeman quantum beats of single rotational levels in /sup 3/B/sub 2/ carbon disulfide
The lowest observed triplet state of carbon disulfide, the R /sup 3/B/sub 2/ state, was directly excited using a pulsed, narrow bandwidth dye laser (0.05 cm/sup -1/). The first reported collision-free lifetimes of this state of CS/sub 2/ were obtained, and the changes in lifetime for single rotational and vibrational levels were observed. The effect of rotation and vibration on the lifetimes indicates that the R /sup 3/B/sub 2/ state has strong spin-orbital coupling with the higher lying V /sup 1/B/sub 2/ state, which gives the R /sup 3/B/sub 2/ state such short lifetimes (2--5 ..mu..s) for a triplet state. A magnetic field was observed to have no effect on the lifetimes, which is consistent with this strong spin-orbital coupling scheme. Zeeman quantum beats were observed on the fluoresence decay curves in a magnetic field. Beat frequencies were obtained as a function of magnetic field strength to obtain permanent magnetic dipole moments for the R /sup 3/B/sub 2/ state vibrational levels. The magnetic dipole moments were found to be independent of rotational angular momentum (N dependence) indicating a strong spin-orbital coupling, consistent with the lifetime data. The collisional depolarization rate was qualitatively observed to be competitive with and slightly faster than electronic quenching.
- Research Organization:
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
- OSTI ID:
- 6098334
- Journal Information:
- J. Chem. Phys.; (United States), Vol. 84:7
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
CARBON SULFIDES
FLUORESCENCE
ZEEMAN EFFECT
ELECTRONIC STRUCTURE
EXCITED STATES
LIFETIME
MAGNETIC FIELDS
ROTATIONAL STATES
CARBON COMPOUNDS
CHALCOGENIDES
ENERGY LEVELS
LUMINESCENCE
SULFIDES
SULFUR COMPOUNDS
640302* - Atomic
Molecular & Chemical Physics- Atomic & Molecular Properties & Theory