Near-Infrared-Absorbing B-N Lewis Pair-Functionalized Anthracene Derivatives: Electronic Structure and Second-Order NLO Properties.

Creating optical materials with linear and nonlinear properties has always been a focus of attention in the scientific community. Recently, Pf (x) displays unusual photophysical properties, such as near-infrared absorption and emission, and transparency in the visible light region, etc. However, from the perspective of improving material performance, its structure-property correlation remains to be fully investigated. Herein, three anthracene derivatives are designed based on Pf(x). By means of density functional theory and time-dependent density functional theory, the electronic structure and nonlinear optical response of Pf(x) and three newly designed anthracene derivatives have been thoroughly explored. This investigation indicates that they show narrow energy gap, near-infrared absorption, large first hyperpolarizability, strong polarization resonance for frequency-dependent hyperpolarizabilities, and derivative 3 is a bipolar transport material. With the aid of depolarization analysis, the unit sphere representation method and the hyperpolarizability density analysis, the origin of nonlinearity was systematically analyzed from both structural and physical perspectives. Due to their large first hyperpolarizability, the investigated derivatives may be referred to as superior second-order nonlinear optical materials and widely used in optoelectronic materials.