DFT investigation of M₂F superalkali doped dodecafluorophenylene (C₁₃H₁₀F₁₂) derivatives with remarkable static and dynamic NLO response

Herein, based on density functional theory (DFT) simulations, the static and dynamic hyperpolarizabilities of the superalkalides based on Janus molecules have been explored. The designed superalkalides M 2 F (F) -DDFP-M 2 F (H) contain Janus based Dodecafluorophenylene (DDFP) molecule doped with superalkalis on both sides acting as both electron acceptors and donors. Thermodynamic stabilities are evident from the negative values of interaction energies, which are observed in the range of −2.96 eV to −3.63 eV. The maximum interaction energy (E int ) obtained is −3.63 eV for Li 2 F (F) -DDFP-Li 2 F (H) complex. The NBO (natural bond orbital) and FMO (frontier molecular orbital) analyses confirm the true superalkalide nature of the designed complexes. FMO analysis further reveals the reduction in energy gap E (H-L) from 10.43 eV (for bare DDFP) to 3.17 eV for the designed superalkalis. Furthermore, NLO response of the studied complexes reveals that the maximum values of polarizability (617 au) and hyperpolarizability are seen for Na 2 F (F) -DDFP-K 2 F (H) (4.25 × 10 4 au) complex, which confirms the remarkable NLO response of newly designed superalkalides. Moreover, frequency dependent analysis indicates that the maximum values of simple harmonic generation (SHG), electro-optical pockel effect (EOPE) and hyper Rayleigh scattering are 7.79 × 10 6 , 2.75 × 10 6 and 4.45 × 10 6 au, respectively. The EOKE and EFISHG values are 6.79 × 10 7 and 7.68 × 10 10 at 1339 nm suggesting significant increase in the NLO response of the reported complexes. These results manifest that our designed complexes might provide new paths towards the exceptionally high performance NLO materials. Moreover, we expect that the present work will provide guidance for designing and synthesis of superalkali based NLO materials in future.