Direct formation of RCI from the gas-phase reaction of thermal atomic chlorine with PbR/sub 4/ (R = CH/sub 3/, C/sub 2/H/sub 5/)

Journal Article · Thu Jan 08 00:00:00 EST 1981 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j150601a019· OSTI ID:6583917

Kikuchi, M; Lee, F S.C.; Rowland, F S

The reactions of chlorine atoms with Pb(CH/sub 3/)/sub 4/ have been studied in the gas phase at 20/sup 0/C and 500 to 5000 torr pressure, using /sup 38/Cl atoms thermalized by multiple collisions with CCL/sub 2/F/sub 2/ after formation by the nuclear reaction /sup 37/Cl(n, ..gamma..)/sup 38/Cl. Approximately 18% of the /sup 38/Cl atoms react with Pb(CH/sub 3/)/sub 4/ by a direct bimolecular substitution mechanism to form CH/sub 3//sup 38/Cl, as in (1): /sup 38/Cl + Pb(CH/sub 3/)/sub 4/ ..-->.. CH/sub 3//sup 38/Cl + Pb(CH/sub 3/)/sub 3/(1). The formation of C/sub 2/H/sub 5//sup 38/Cl is observed for thermal /sup 38/Cl reaction with Pb(C/sub 2/H/sub 5/)/sub 4/: /sup 38/Cl + Pb(C/sub 2/H/sub 5/)/sub 4/ ..-->.. C/sub 2/H/sub 5//sup 38/Cl + Pb(C/sub 2/H/sub 5/)/sub 3/(2). About 5% of the /sup 38/Cl atoms undergo hot substitution reaction with CCl/sub 2/F/sub 2/, and the remaining /sup 38/Cl atoms (> 75%) presumably react chiefly by abstraction of H from PbR/sub 4/, as in (3): /sup 38/Cl + Pb(CH/sub 3/)/sub 4/ ..-->.. H/sup 38/Cl + (CH/sub 3/)/sub 3/PbCH/sub 2/(3). The relative rates of reactions 1 and 3 have been measured in competition with addition to C/sub 2/H/sub 4/ and C/sub 2/H/sub 2/, and the absolute reaction rates estimated from the known rates of the addition reactions. The rate constants are k/sub 1/ = (3.0 +- 0.5) x 10/sup -11/cm/sup 3/ molecule /sup -1/s/sup -1/ and k/sub 3/ = (1.3 +- 0.3) x 10/sup -10/cm/sup 3/ molecule/sup -1/s/sup -1/. The reactivity towad H abstraction is approximately the same per C-H bond for reaction with Pb(CH/sub 3/)/sub 4/ and C/sub 2/H/sub 6/. The reaction rates with Pb(C/sub 2/H/sub 5/)/sub 4/ appear to be even faster than with Pb(CH/sub 3/)/sub 4/ for both the substitution and abstraction process.

• Research Organization: Univ. of California, Irvine
• OSTI ID: 6583917
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 85:1; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400701* -- Radiochemistry & Nuclear Chemistry-- Hot-Atom Chemistry
BARYONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHEMICAL REACTION KINETICS
CHEMISTRY
CHLORINE 38
CHLORINE ISOTOPES
ELEMENTARY PARTICLES
FERMIONS
FLUIDS
GASES
HADRONS
HOT ATOM CHEMISTRY
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
KINETICS
LEAD COMPOUNDS
LIGHT NUCLEI
LOW PRESSURE
MEDIUM PRESSURE
MEDIUM TEMPERATURE
MINUTES LIVING RADIOISOTOPES
NEUTRONS
NUCLEI
NUCLEONS
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
RADIOCHEMISTRY
RADIOISOTOPES
REACTION KINETICS
SECONDS LIVING RADIOISOTOPES
TEL
THERMAL NEUTRONS