Introduction: A graph is supposed to be regular if all vertices have equal degree, otherwise irregular.
Materials and Methods: Polycyclic aromatic hydrocarbons are important combusting material and considered as
a class of carcinogens. These polycyclic aromatic hydrocarbons play an important role in graphitisation of medical
science. A topological index is a function that assigns a numerical value to a (molecular) graph that predicts
various physical, chemical, biological, thermodynamical and structural properties of (molecular) graphs. An irregular
index is a topological index that measures the irregularity of atoms with respect to their bonding for the
chemical compounds which are involved in the under studying graphs.
Results and Discussion: In this paper, we will compute an analysis of distance based irregular indices of polycyclic
aromatic hydrocarbons. A comparison among the obtained indices with the help of their numerical values
and the 3D presentations is also included. The efficient and steady indices of polycyclic aromatic hydrocarbons
are addressed in the form of their irregularities.
Conclusion: Connection based study of the molecular graphs is more suitable than the degree based irregularity