Positronium reactions in micellar systems. [Effect of micellar system on reaction rates]

Journal Article · Wed Nov 09 04:00:00 EST 1977 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00465a018· OSTI ID:5244084

Jean, Y; Ache, H J

The rate constants for Ps reactions with nitrobenzene and CuCl/sub 2/ in various micellar systems such as sodium dodecyl sulfate, sodium octyl sulfate and sulfonate, hexadecyltrimethylammonium bromide and chloride, hexadecylpyridinium chloride, and tergitol were measured. The results show that in most cases the Ps reactivity toward nitrobenzene is significantly reduced when the latter is located in the micellar phase as compared to the homogeneous aqueous phase. On the other hand, the observed reaction constants do not coincide with the constants measured for Ps-nitrobenzene in the corresponding alkanes either, with the exception of sodium octyl sulfate and sulfonate. Since Ps-nitrobenzene reaction rate constants were found to be sensitive to the environment in which they occur, these results may suggest that the nitrobenzene probe molecule is located in the Stern layer where it forms complexes with the various head groups, in which form its reactivity toward Ps will be decreased. An exception could be the sodium octyl sulfate system, where nitrobenzene may be in an aqueous environment, or the sodium octyl sulfonate where the nitrobenzene may reside in a hydrocarbon-like environment. In micellar solutions containing Cu/sup 2 +/ ions, no change in the Ps rate constants is observed in the case of the neutral tergitol or the cationic hexadecylpyridinium chloride micellar systems, whereas in the presence of the anionic micelles, sodium dodecyl sulfate or sodium octyl sulfate or sulfonate, which easily adsorb Cu/sup 2 +/ ions, the rate constants drastically drop.

• Research Organization: Virginia Polytechnic Inst. and State Univ., Blacksburg
• OSTI ID: 5244084
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 99:23; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400301 -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
640303* -- Atomic
Molecular & Chemical Physics-- Positronium
Muonium
& Muonic & Mesic Atoms & Molecules
74 ATOMIC AND MOLECULAR PHYSICS
CHEMICAL REACTION KINETICS
CHLORIDES
CHLORINE COMPOUNDS
COPPER CHLORIDES
COPPER COMPOUNDS
COPPER HALIDES
HALIDES
HALOGEN COMPOUNDS
KINETICS
MICELLAR SYSTEMS
NITRO COMPOUNDS
NITROBENZENE
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
POSITRONIUM
REACTION KINETICS
TRANSITION ELEMENT COMPOUNDS