具有k个悬挂点的化学图的调和指数

The Harmonic Index on Chemical Graphs with k Pendant Vertices

调和指数是著名的Randic'指数的一种变形形式,研究表明该指数能有效地预测化合物的物理化学性质.对具有固定悬挂点数目的化学图的调和指数进行了研究.采用图论的方法,得到了具有n个顶点,以及m(m≥n)条边和k(k>0)个悬挂点的化学图的调和指数的一个上界,并刻画了极图.

As a variant of the well known Randic’index,the harmonic index has been proven to be a valuable predictive index in the study of the physical and chemical properties of compounds.The harmonic index of chemical graph with fixed pendant vertices was investigated.By using the method of graph theory,an upper bound on the harmonic index for all chemical graphs of order n with m≥n edges and k>0 pendant vertices was presented,and the extremal graphs were determined.