Ran Qin, Yang Chung Hsin, Lee Yuan T, Lu I-Chung, Shen Guanlin, Wang Ling, Yang Xueming
Department of Chemistry, University of California at Santa Barbara, Santa Barbara, CA 93106, USA.
J Chem Phys. 2005 Jan 22;122(4):44307. doi: 10.1063/1.1839865.
The dynamics of the F atom reaction with propyne (CH(3)CCH) has been investigated using a universal crossed molecular beam apparatus. Two reaction channels have been clearly observed: H+C(3)H(3)F and HF+C(3)H(3). The substitution of F for H occurs mainly via a complex formation mechanism, producing reaction products with some contribution from a direct reaction mechanism. The HF product, however, appears to be dominantly forward scattered relative to the F atom beam direction, suggesting that the HF formation occurs via a direct abstraction mechanism. Branching ratios for the two observed reaction channels are also determined. The H formation channel is found to be the major reaction pathway, while the HF formation channel is also significant. From the measurements of DF versus HF products from the F atom reaction with deuterated propyne, the H atom picked up by the F atom in the reaction with normal propyne seems to come mostly from the CH(3) group. In addition, the H atom produced in the H atom formation channel appears to be mostly from the CH(3) group with some contribution from the CCH group.
利用通用交叉分子束装置研究了氟原子与丙炔（CH(3)CCH）的反应动力学。清晰地观察到了两个反应通道：H + C(3)H(3)F和HF + C(3)H(3)。氟取代氢主要通过络合物形成机制发生，反应产物有部分来自直接反应机制的贡献。然而，HF产物相对于氟原子束方向似乎主要向前散射，这表明HF的形成是通过直接提取机制发生的。还确定了两个观察到的反应通道的分支比。发现H形成通道是主要反应途径，而HF形成通道也很重要。通过测量氟原子与氘代丙炔反应生成的DF与HF产物，氟原子在与普通丙炔反应中夺取的氢原子似乎大多来自CH(3)基团。此外，在H原子形成通道中产生的H原子似乎大多来自CH(3)基团，CCH基团也有一些贡献。
