Collisional energy transfer from highly excited CS{sub 2} and SO{sub 2}

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:215133

Chimbayo, A; Barker, J R ^[1]; Toselli, B M ^[2]

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1. Univ. of Michigan, Ann Arbor, MI (United States)
2. Universidad Nacional de Cordoba (Argentina)

We have used Time Dependent Thermal Lensing (TDTL) to monitor energy deposition from laser excited CS{sub 2} and SO{sub 2} in baths of rare gas at pressures from 50 Torr to 600 Torr. The experimental TDTL signals are simulated by using a unified theory of Thermal lensing and an assumed expression for k{sub e}(E), the energy dependent rate coefficient for V-T energy transfer. By empirically adjusting the parameters and form of k{sub e}(E) to obtain the best simulations, we find energy transfer to be significantly more efficient when the collision frequency is low. These results are interpreted in terms of a phenomenological model in which the excited species loses energy in a collision and is left with a nascent intramolecular energy distribution which cannot transfer energy efficiently by collisions. This distribution then undergoes collision free relaxation with a single time constant to one which is more favorable for subsequent collisional energy transfer. If the next collision occurs before the intramolecular relaxation is complete, energy transfer is less efficient.

• OSTI ID: 215133
• Report Number(s): CONF-950801--
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CARBON SULFIDES
COLLISIONS
DEPOSITION
ENERGY TRANSFER
RELAXATION
SULFUR DIOXIDE