Linear and second‐order nonlinear optical properties of B,N‐embedded double hetero[7]helicenes

Abstract

AbstractIn this paper, the linear and second‐order nonlinear optical properties of the reported B,N‐embedded double hetero[7]helicene and four new designed helicenes are systematically investigated with the aid of density functional theory. This research demonstrates that the introduction of NH2 unit, combination of NH2 and NO2 units or π bridge reduces the energy gap, changes the HOMO distribution and red‐shifts low‐energy absorption wavelength. And the insertion of combination of NH2 and NO2 units or π bridge also remarkably increases the first hyperpolarizability. Considering the smaller electronic reorganization energy and the larger static first hyperpolarizability, the studied helicenes may be potential outstanding candidates for electronic transport materials and strong second‐order nonlinear optical materials.