Static, dynamic nonlinear optical (NLO) response and electride characteristics of superalkalis doped star like C₆S₆Li₆

In search of excellent nonlinear optical (NLO) materials, new type of M₃O@C₆S₆Li₆ (M = K, Na, Li) electrides are set forth herein. The geometric, electronic and nonlinear optical properties of these electrides are evaluated by using density functional theory calculations. All the considered complexes have interaction energies in the range of -42.86 to -45.56 kcal/mol that validate their thermodynamically stability. The NBO charge analysis is performed to confirm the charge transfer between M₃O and C₆S₆Li₆. The highest amount of electronic charge transfer (0.92 |e|) is seen in K₃O@C₆S₆Li₆ electride. The frontier molecular orbitals (FMOs) and density of states (DoS) analyses are implemented to further rationalize the electronic properties. The remarkable polarizability (α_o) and static first hyperpolarizability (β_o) observed for these complexes validate their excellent nonlinear optical response. The highest β_o (2.98×10⁵ au) is obtained for Li₃O@C₆S₆Li₆ electride. The frequency-dependent first and second hyperpolarizability coefficients along with dipole dependent hyperpolarizability are also analyzed to get insight of NLO response under variational frequencies. Furthermore, the Hyper-Rayleigh Scattering coefficient (β_HRS) of these complexes is investigated to provide information required for experimental point of view of NLO response. This study will contribute towards the development of more stable superalkalis doped electrides having pronounced NLO response.