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

Abstract

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 (αo) and static first hyperpolarizability (βo) observed for these complexes validate their excellent nonlinear optical response. The highest βo (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 (βHRS) 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.