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Updated: May 19, 2026

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Variable temperature rate studies for the reaction H3O(+) + (C2H2)2 measured with a coaxial molecular beam radio
Mark A Smith1, Bing Yuan, Andrei Sanov
1Department of Chemistry and Biochemistry, University of Arizona, 1306 East University Boulevard, Tucson, Arizona 85721, USA. markasmith@nsm.uh.edu
Abstract:
The independent molecule and ion temperature dependence of the rate coefficient for the H(3)O(+) and (C(2)H(2))(2) reaction producing C(2)H(5)O(+) are determined using a coaxial molecular beam radio frequency ring electrode ion trap (CoMB-RET). The H(3)O(+) temperature is varied from 25 to 170 K, while the equilibrated C(2)H(2)/(C(2)H(2))(2) beam temperatures sampled are 160, 180, 200, and 220 K. The rate coefficient of the H(3)O(+) + (C(2)H(2))(2) reaction is determined to be 4.0 × 10(-10) × (T(react)/300)(-2.5) in the reaction temperature range of T(react) = 114-187 K. The H(3)O(+) and C(2)H(2) radiative association reaction is found to have a rate coefficient below 1 × 10(-13) cm(3)·s(-1) at 187 K. This result is consistent with Herbst's experimental determination.
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