烷烃异构体的结构排序与热力学性质的变化规律

应用分子链状片断(C-C-C, C-C-C-C, C-C-C-C-C)数P2、P3、P4研究了烷烃异构体系列的结构排序及其热力学性质的规律性。每个烷烃分子表达为二维平面(mP2+P4, P3)上的一个点(对辛烷, m=2, 壬烷m=4, 癸烷m=5), 沿着坐标轴方向连结相同m点, 得到相应烷烃的异构体周期表。在此基础上, 提出了分子异构体序数的概念, 并分析了多种热力学性质的变化趋势及其对结构的依赖关系。

Ordering of structures as a basis for searches for regularities in thermodynamic properties in isomers of alkanes

Paths of length 2, 3 and 4 appear to dominate variations in isomers of alkanes when various thermodn. properties are compared. In the present work, each isomer can be represented as a point in a two-dimensional space (mP2 + P4, P3) (m is 2, 4 and 5 octanes, nonanes, and decanes resp.). By joining adjacent points which have the same m along the coordinate lines authors obtain grid graphs depicting interrelations of isomers, which are defined in the tables of isomeric structures. Basing on the tables, the concept, isomeric no. is proposed. By replacing each of the structures on the tables with the corresponding numerical value for the selected mol. property, one could observe the regularities in the trends in a collection of isomers studied for selected properties.5