Studying the geometrical, electronic and spectroscopic properties comparative between corannulene and coronene: Via DFT study

The geometrical, spectroscopic, electronic, and thermo-dynamic coronene characterization (C 24 , C 24 O), and Corannulene (C 20 , C 20 O) have been investigated and contrasted in the present study. Besides the electronic parameters like HOMO, and LUMO energy levels and resulting energy gap, important thermodynamic properties like Gibbs free energy, entropy, enthalpy, and heat capacity have been assessed. IR and Raman spectra have also been used for analyzing vibration characteristics. The computational analysis utilized Density Functional Theory (DFT) with 6–311 G** basis set and B3LYP hybrid functional, incorporating Becke’s three-parameter exchange and Lee–Yang–Parr correlation techniques. The band gap is found of Corannulene (C 20 - C 20 O) equals (3.7 eV −2.1 eV), while the E g of Coronene (C 24 - C 24 O) equals (3.5 eV – 1.68 eV), respectively. IR and Raman intensity of Corannulene (C 20 , C 20 O) and Coronene (C 24 , C 24 O) are computed, experimental results show that Longitudinal Optical vibration mode occurs at 1585 cm⁻¹ for graphene and 1582 cm⁻¹ for graphene oxide, which aligns well with theoretical predictions. Key thermodynamic quantities such as Gibbs free energy and enthalpy, entropy, and heat capacity variations were computed for C 20 , C 20 O, C 24 , and C 24 O at room temperature. Gibbs free energy and enthalpy were observed to decrease in negative sign when an oxygen atom was present. This was because the system's size increased and the atoms' interactions increased.