摘要
通过一些晶体结构的实例指出,目前广泛采用的质心距小于0.4 nm的判据,在许多情况下并不能正确反映物质中的芳环堆积现象.为了正确判断在平行的芳香化合物之间是否存在近距离的芳环堆积现象,通过理论推算,给出了合理的判断依据:环平面的间距显著小于0.36 nm的范德华厚度,相邻芳环在平面法线方向的投影相互重叠或部分重叠,以上两者需同时满足.晶体学采用的是以晶胞为基础的斜坐标系,为了正确计算斜坐标系中平行平面的间距,利用转换矩阵,将斜坐标转换成归一化的笛卡儿坐标,在此基础上得出平行芳环之间面间距的正确计算方法.
With several examples of single crystal structures of compounds incorporating aromatic rings, the criterion of the centroids distance of 0.4 nm between parallel rings was proved to be unreliable in some cases. In order to correctly judge if aromatic stacking exists between two parallel or nearly parallel aromat- ic compounds, an appropriate criterion was proposed to be that： significantly shorter face-to-face separation than the van der Waals thickness of 0.36 nm for aromatic ring, and overlapped or partially overlapped arrangement between aromatic rings in the project direction along the normal of the ring plane. After transformation from crystallographic coordinates to orthogonal coordinates, a calculation method for the face-to-face separation between parallel aromatic rings was given.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2008年第12期2228-2232,共5页
Journal of Zhejiang University：Engineering Science
基金
国家自然科学基金资助项目(20443003)
关键词
芳环堆积
芳环堆积的判据
质心距
平面间距
投影重叠
aromatic stacking
criterion for aromatic stacking
centroids distance
face-to-face separation
overlapped project
