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arXiv · 1001.5342

Reactions of C$_2$({\it a}$^3Pi_u$) with selected saturated alkanes: A temperature dependence study

Renzhi Hu·Qun Zhang·Yang Chen
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Abstract

We present a temperature dependence study on the gas phase reactions of the C$_2$({\it a}$^3Pi_u$) radical with a selected series of saturated alkanes (C$_2$H$_6$, C$_3$H$_8$, n-C$_4$H$_10$, i-C$_4$H$_10$, and n-C$_6$H$_14$) by means of pulsed laser photolysis/laser-induced fluorescence technique. The bimolecular rate constants for these reactions were obtained between 298 and 673 K. A pronounced negative temperature effect was observed for n-C$_4$H$_10$, i-C$_4$H$_10$, and n-C$_6$H$_14$ and interpreted in terms of steric hindrance of the more reactive secondary or tertiary C-H bonds by less reactive CH$_3$ groups. Detailed analysis of our experimental results reveals quantitatively the temperature dependence of reactivities for the primary, secondary, and tertiary C-H bonds in these saturated alkanes and further lends support to a mechanism of hydrogen abstraction.

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Renzhi Hu, Qun Zhang, Yang Chen. 2010-05-01. Reactions of C$_2$({\it a}$^3Pi_u$) with selected saturated alkanes: A temperature dependence study. https://doi.org/10.1063/1.3400070

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