Excited state dynamics of electronically-excited UF6 in the presence of added gases

156

EXCITED

STATE

DYNAMICS

OF ELECTRONICALLY-EXCITED

UF s IN THE PRESENCE

OF ADDED

GASES F. 8. Wampler, University Mexico

of California,

87545

and W. W. Rice

R. C. Oldenborg

Los Alamos

Scientific

Laboratory,

Los Alamos,

New

(U.S.A.)

by selected alkanesltas been The removal of *UFs (A-state) molecules R/mol-s) The following rate constants (units of 10 investigated at 25°C. were evaluated: iso-CbFlv, 0.0432 + 0.0115; n-CrFlo, 0.0764 * 0.020; CZFB, 0.0192 + 0.0052; CHI,, 0.0612 + 0.0061; C2H6,-3.78 + 0.60; CsHs, 5.08 + 0.60; 4.17 i 1.15; neo-CsHl2, 6.59 f 0.93; n-CbHlo, 5.05 f 0.78; iso-CsHlo, CF2H-CFzH, 0.0729 f0.0074; and CFZH-CFHZ, 0.149 EF~-cH~, 0.0385 f O.Om; The perfluoro-alkane quenching of *LlFs proceeds via physical mechf 0.015. The other alkane quenching reactions are consistent with a chemical anism. Repmechanism which involves removal of two hydrogens from the alkane. resentative Stern-Volmer plots are depicted in the figure below.

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