CACTI WITH EXTREMAL PI INDEX
By Chunxiang Wang, Shaohui Wang, Bing Wei. 2016
52 citations recorded by the source corpus.
The vertex PI index $PI(G) = sum_{xy in E(G)} [n_{xy}(x) + n_{xy}(y)]$ is a distance-based molecular structure descriptor, where $n_{xy}(x)$ denotes the number of vertices which are closer to the vertex $x$ than to the vertex $y$ and which has been the considerable research in computational chemistry dating back to Harold Wiener in 1947. A connected graph is a cactus if any two of its cycles have at most one common vertex. In this paper, we completely determine the extremal graphs with the greatest and smallest vertex PI indices mong all cacti with a fixed number of vertices. As a consequence, we obtain the sharp bounds with corresponding extremal cacti and extend a known result.
Subfields: Computational Theory and Mathematics, Geometry and Topology
View Paper: https://www.semanticscholar.org/paper/bcbde0f1a2439687d9e2292edc7a0b3026d9a7d4
Citations in the corpus
- Distance‐based topological descriptors for measuring the π‐electronic energy of benzenoid hydrocarbons with applications to carbon nanotubes (2020, unknown): “For a graph Γ , the PI index is defined as follows: Wang et al 31 studied the extremal cacti graphs with respect to the PI index.”