The following set of keywords was employed in the MOPAC calculations, in addition to the PM7 method, to achieve an optimal balance between computational efficiency and accuracy: PRECISE, GNORM=0.001, SCFCRT=1.D-8, DISPERSION=D3H4, H-PRIORITY, AUX, and ITRY=200. These keywords enforce stricter convergence criteria for the self-consistent field (SCF) procedure, include long-range dispersion corrections, prioritize the treatment of hydrogen atoms, enable auxiliary basis functions, and increase the maximum number of SCF iterations.