新建议的拓扑指数F′考虑了分子的图形特征,顶点原子的性质,顶点原子与相邻原子的键合情况,并以矩阵的形式把这些特征表达出来。n个原子构成的体系通过矩阵运算可得到包含n项的多项式,其中,每一项对应一个顶点原子对F′的贡献,从而赋予了拓扑指数F′明确的物理意义。用F′研究一些烷基苯的标准生成焓,得到了令人满意的结果。 The newly proposed topological index F ’takes into account the graphical features of the molecules, the nature of the vertex atoms, the bonding of the vertex atoms to neighboring atoms, and expresses these characteristics as a matrix. The system composed of n atoms can be obtained by matrix operation and contains polynomials of n terms, each of which corresponds to the contribution of one vertex atom to F ’, thus giving the explicit physical meaning of the topological index F’. Using F ’to study the standard enthalpies of formation of some alkylbenzenes, satisfactory results were obtained.