Optimizing Nonlinearity in C6O6Li6-Doped Alkalides via Group I/III Doping for Unprecedented Charge Transfer and Breakthrough in Optoelectronics

Abstract

The design and synthesis of nonlinear optical (NLO) materials are fast-growing fields in optoelectronics. Keeping in view the high demand of newly designed materials with superior optoelectronic characteristics, herein we have investigated doping Group-IIIA elements (namely, B, Al and Ga) on alkali metals (AM = Li, Na and K) supported C6O6Li6 (AM@C6O6Li6) complexes to enhance the NLO response. The AM-C6O6Li6 complexes sustained their structural features after interaction with Group-IIIA elements. Interaction energies as high as -109 kcal mol-1 demonstrated a high thermodynamic stability of the complexes. An exceptional charge transfer behavior is predicted in these complexes where the electronic density of Group-III metals shifts toward the alkali metals, making such complexes as alkalides. The π conjugation of C6O6Li6 withdraws excess electrons from Group IIIA metals in these alkalides, which are subsequently transferred to Group IA metals. The frontier molecular orbitals (FMOs) energy gap of AM-C6O6Li6 is notably reduced after alkalide formation. UV-Visible analysis explicitly described the bathochromic shift inside the alkalides. The first hyperpolarizability (βo) is calculated to confirm the NLO properties of these alkalides. B-C6O6Li6-K has the highest βo value of 1.75×105 au. These properties reflect the promising NLO response of our designed alkalides and their use in the field of optics.