Reactivity Of C2H5+ with Benzene: Formation of Ethylbenzenium Ions and Implications for Titan's Ionospheric Chemistry
Abstract
The reaction of ethyl cation with benzene ha's been investigated in a combined experimental and theoretical approach. Under single collision conditions, proton transfer affording protonated benzene concomitant with neutral ethene represents the major reaction channel.
From pressure-dependent measurements, an absolute cross section of 7 +/- 2 angstrom(2) at hyperthermal energies (about 1.0 eV in the center of mass frame) is derived for this channel, from which a phenomenological rate constant of about 2.9 x 10(-10) cm(3) s(-1) is estimated at low energies. The energy behavior of the cross section as well as several side reactions leading to C-C coupling imply that the reaction Of C2H5+ with CA proceeds via a long-lived association product, presumably the covalently bound protonated ethylbenzene (ethylbenzenium ion).