Excited state kinetics in high pressure gas mixtures of krypton and chlorine and in krypton and xenon

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1984

OSTI ID:6855409

Durret, M G

Formation and decay of KrCl/Kr/sub 2/ and (KrXe) + excited states have been studied by following the time dependence of the various fluorescence bands. The Cl/sup */ is found to react very rapidly with krypton to form KrCl in a vibrationally excited state. Above approx.75 torr the formation of the radiation states is found to be rate limited by vibrational relaxation (K/sub vib/ = 8.6 +/- 0.4 x 10/sup -11/). Following vibrational relaxation the B and C states are completely mixed and decay with a mixed state radiative lifetime of 5.4 +/- .1 ns. The mixed state is strongly quenched by chlorine (K = 7.6 +/- 5 x 10/sup -10/) and also by krypton in a three body process (K = 1.15 +/- .03 x 10/sup -30/) which presumably leads to production of Kr/sub 2/Cl. The Kr/sub 2/Cl emission, monitored at 325 nm, is strongly quenched by chlorine (K = 6.7 x 10/sup -10/) but only weakly, if at all, by krypton (K less than or equal to 2.27 x 10/sup -14/). The Kr/sub 2/Cl is found to have an anomalously long radiative lifetime (>1..mu..sec). The time dependence of 4900 A emission in Kr-Xe mixtures was also measured following pulsed excitation by a low intensity, high energy electron beam. The time dependence was obtained at pressures of 500 to 10,000 torr and at temperatures ranging from 30 to 40/sup 0/C. The population of the upper ionic state of the transition is found to be governed by a dissociation recombination reaction which establishes an equilibrium between the heteronuclear molecular ion and its associated atomic ion. The measured dissociation and recombination rate constant for this reaction are 1.94 +/- 12 x 10/sup -11/ and 5 +/- 2 x 10/sup 32/ respectively. The radiative lifetime was determined to be (46 +/- 4 ns). The temperature dependence of the dissociation rate constant yields an activation energy of 0.08 +/- 0.02 eV.

• Research Organization: Rice Univ., Houston, TX (USA)
• OSTI ID: 6855409
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
500200 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
BEAMS
BINARY MIXTURES
CHEMICAL REACTION KINETICS
CHLORINE
DATA
DISPERSIONS
ELECTROMAGNETIC RADIATION
ELECTRON BEAMS
ELEMENTS
EMISSION SPECTROSCOPY
ENERGY LEVELS
EXCITED STATES
EXPERIMENTAL DATA
FLUIDS
FLUORESCENCE SPECTROSCOPY
GASES
HALOGENS
HIGH PRESSURE
INFORMATION
KINETICS
KRYPTON
LEPTON BEAMS
LIFETIME
LOW PRESSURE
MEDIUM PRESSURE
MIXTURES
NONMETALS
NUMERICAL DATA
PARTICLE BEAMS
RADIATIONS
RARE GASES
REACTION KINETICS
SPECTROSCOPY
ULTRAVIOLET RADIATION
XENON