Evidence for Insertion Mode Reaction of Energetic Carbon-11 with Oxygen

Abstract

Atomic carbon-11 produced by two different nuclear transformations reacted with 0 2 to yield "CO and "C0 2 . The extent of radiolytic conversion of "CO to "C0 2 contributing to the yield of "C0 2 was established by absorbed dose and irradiation time experiments in gas phase CH 4 + 4.5% 0 2 , c-C 4 F" + 4.5% 0 2 , and ultrahigh purity 0 2 systems. Yield measurements extrapolated to the minimum dose required to assay the "C indicates the insertion mode of reaction of "C with 0 2 in the collision complex gives rise to a 5.6±0.6% absolute yield of "C0 2 . Energetic "C in 3 P electronic state may give rise to both "CO and "C0 2 , while thermalized "C in the 3 P ground state gives rise only to "CO. When a halogen substituent is present on a substrate, then energetic "C ('D, 1 S) can be converted to hot "C ( 3 P) that can then undergo insertion reactions into the π electron system of 0 2 .

In-Situ Radiocarbon Production by Neutrons and Muons in an Antarctic Blue Ice Field at Scharffenbergbotnen: A Status Report

“…Such equilibrium is not known and may depend on local ice conditions. Irradiation experiments in which 11 C was produced showed a CO 2 fraction increasing with the applied dose (Lambrecht 1997). …”