链烷烃标准熵的拓扑研究

Topological Research of Standard Entroplies of Alkanes

根据核磁共振的峰数及Randic的碳原子支化度 ,提出了碳原子特征值 .基于连接矩阵和碳原子特征值 ,建立新的连接指数 mY .其中的 0阶连接性指数0 Y很容易计算 ,且对烷烃异构体有很强的区分能力 .将 15 7种气态链烷烃的标准熵与其0 Y相关联 ,R =0 .9985 ,属于优级模型 .与Randic指数的0 χ及倪才华等提出的信息拓扑指数Ix、IW 比较 ,0

According to the peak numbers of the nuclear magnetic resonance and the Randic embranchment degree of the carbon atom, the carbon atom's characteristic value is derived. A novel connectivity indexes Y-m based oil the adjaceney matrix and the characteristic worth of the carbon atom is constructed. The zeroth-order connectivity indexes 0 1 among the connectivity index Y-m are very easy to be calculated and have good discrimination between isomeric alkalies. The zeroth-order connectivity indexes Y-0 of 157 alkanes are calculated and correlated with the standard entropies of the alkanes, and the property is well modeled ( R = 0.9985). It is concluded that the index 0 V bears good structure selectivity and property relativity compared with Randle's (0)chi and Ni Caihua's topological information index which provids a valid method for predicting the standard entropies of alkanes.