Photocatalysis mechanism has acquired an egregious amount of consideration for a wide spectrum of utilizations in the environmental and energy fields. The potential applications which are rigorously associated with environmental reclamation and the latest energy developments include water splitting, pollutant decomposition, and photocatalytic diminution of CO2. This study deals with the discussion of the crystal structure of the polyphenylene network for photocatalysis PPN [ m ] and the computation of some degree-based topological indices which are very beneficial for estimating the reactivity of the corresponding compounds. Particularly, we extend this computation to the analysis of the thermodynamic properties namely entropy and heat of formation which could be beneficial in the structure amendment PPN [ m ] for effective implementation. [ABSTRACT FROM AUTHOR]