Radical reactivity and Q-e values of methyl α-(trifluoromethyl)acrylate
Radical reactivity and Q-e values of methyl α-(trifluoromethyl)acrylate
复制标题
α-(三氟甲基)丙烯酸甲酯的自由基反应性和Q-e值
DOI：
10.1021/ma00140a056
复制
发表时间：
1984
期刊：
影响因子：
5.5
通讯作者：
R. Engelbrecht
中科院分区：
文献类型：
--
作者：
Hiroshi Ito;B. Giese;R. Engelbrecht
讨论在记录三维电子衍射图样时遇到的两个实验困难是由于辐射敏感的聚合物晶体寿命短造成的。困难在于，首先，如何快速和准确地定向晶体，使得晶轴之一与测角仪的倾斜轴重合，其次，找到适当的倾斜角，以使感兴趣区域的衍射斑点精确地位于记录平面中。对poly-（t-CDS）的hkh和h，k，2 h区的电子衍射图的检查（参考文献11的图2a）表明，这些实验问题尚未完全解决。尽管存在上述问题，但来自聚（t-CDS）11的电子衍射数据在所研究的每个区域中提供了一致的结果。三种不同的微晶似乎都有大约2的轻微弯曲。从这些非常薄的晶体衍射光束的振幅轻微的动态散射的影响，确认的Kine-matic的结构分析，Rémillard和Chanzy 11是适当的。
DiscussionThe two experimental difficulties encountered when recording three-dimensional electron diffraction patterns arise from the short life span of the radiation-sensitive polymeric crystals. The difficulties are, first, how quickly and accurately one orients a crystal so that one of the crystallographic axes is coincident with the tilt axis of the goniometer and, secondly, finding the proper tilt angle to have the diffraction spots of the zone of interest exactly in the recording plane. An examination of the electron diffraction patterns of the hkh and h, k, 2h zones of poly-(t-CDS)(Figure 2a of ref 11) indicates that these experimental problems have not been perfectly resolved. In spite of the problems described above, the electron diffraction data from poly (t-CDS) 11 provide consistent results in each zone studied. The three different microcrystals appear to have each a slight bend of about 2. The diffracted beam amplitudes from these very thin crystals are slightly affected by dynamical scattering, confirming that the kine-matic structure analysis of Brisse, Rémillard, and Chanzy11 is appropriate.