The kinetics of the reactions of atomic chlorine with ethane and propane have been studied in a continuous supersonic flow reactor over the range 48 K e T e 167 K. Chlorine atoms were produced by microwave discharge upstream of the Laval nozzle and were probed in the vacuum ultraviolet wavelength range around 138 nm by resonance fluorescence. The reaction of Cl with ethane has been found to exhibit a positive temperature dependence, with a rate coefficient decreasing from (4.3 ( 0.6) × 10-11 cm3 molecule-1 s-1 at 167 K to (2.9 ( 0.3) × 10-11 cm3 molecule-1 s-1 at 48 K and deviates from true Arrhenius behavior below 120 K. In contrast, the rate coefficient for the reaction of Cl with propane has been found to have a constant value of (1.4 ( 0.2) × 10-10 cm3 molecule-1 s-1 over the same temperature range. The expressed uncertainties are the combined statistical (a single standard deviation from the mean) and systematic (estimated at 10%) uncertainties.
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机译：在连续超声速反应器中，研究了在48 K e T e 167 K范围内原子氯与乙烷和丙烷的反应动力学。氯原子是通过在Laval喷嘴上游通过微波放电产生的，并在真空中进行了探测。紫外荧光波长范围约为138 nm。已发现Cl与乙烷的反应表现出正温度依赖性，速率系数从167 K下的（4.3（0.6）×10-11 cm3分子-1 s-1降低到（2.9（0.3）×10-在48 K时11 cm3分子-1 s-1且在120 K以下时偏离真实的Arrhenius行为。相反，发现Cl与丙烷反应的速率系数的常数为（1.4（0.2）×10）在相同温度范围内-10 cm3分子-1 s-1。表示的不确定度是统计上的不确定性（与平均值相比的单个标准差）和系统性不确定性（估计为10％）。
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