Mulliken Electrophilc Indices: The Mulliken electrophilic indices (Figure ) reveal that platinum in the Pt-doped phenalene (Table ) carries a partial positive charge of 0.101, whereas the bonding carbons (C3, C5, and C7) have much smaller partial charges of 0.017. This charge disparity plays a crucial role in enhancing the catalytic efficiency of the system. The relatively higher positive charge on platinum indicates that it acts as a strong electrophile, effectively attracting electron density from the nearby carbons. This promotes the activation of adsorbed hydrogen atoms during the HER, facilitating efficient proton reduction. The electron density withdrawal from the carbon atoms makes them slightly more nucleophilic, creating a synergistic interaction with platinum, which enhances the overall catalytic activity by lowering the energy barrier for hydrogen desorption. This electrostatic configuration significantly improves the catalyst's performance, allowing for a lower overpotential and higher current densities in HER.