On analysis of heat of formation and entropy measures for indium phosphide

A chemical graph represents a chemical or molecular compound in the form of a graph. The vertex set of the chemical graph contains the atoms or molecules of the compound while the edge set comprises of the bonding between the molecules or atoms. In this paper, we compute various connectivity indices based on degrees of vertices of chemical graph of Indium Phosphide (InP) including general Randić, hyper Zagreb and redefined Zagreb indices etc. Afterwards, we calculate the physical measures such as entropy and heat of formation of InP. We fit curves between different indices and the thermodynamical properties namely heat of formation and entropy by using MATLAB through different methods based on linearity and non-linearity. The performance of the method is tested using root mean square error, the sum of squared errors or R². Furthermore, we give graphical representations of these indices. These mathematical frameworks might provide a way to study the thermodynamical properties of the chemical structure of InP at different conditions which will assist to comprehend the relationship between system dimension and these measures.