Three-in-One Strategy Constructing a Series of Hybrid Tetrahedral Motif-Based Selenides with Balanced Second-Order Nonlinear Optical Performance.

Concurrently achieving suitable second harmonic generation (SHG) effect and high laser-induced damage threshold (LIDT) is challenging for infrared nonlinear optical (NLO) materials. Here, a series of pentanary infrared NLO materials CsMIIIMIVSnSe6 (MIII = Ga, In; MIV = Si, Ge) have been obtained by a three-in-one strategy, viz. three kinds of elements (MIII, MIV, and Sn) in one position, which is first adopted to design NLO materials. Their three-dimensional structures are constructed by the MQ4 (M denotes MIII, MIV, and Sn) tetrahedral units. They exhibit promising hybrid NLO properties, witnessed by their moderate/large SHG effects of 0.52, 0.98, 1.05, and 1.12 × AgGaS2, and high powder LIDT values of 6.9, 4.1, 8.1, and 5.4 × AgGaS2, respectively. These NLO properties are well verified by the DFT calculation results. The three-in-one strategy of designing high-performance infrared NLO materials will stimulate more investigations in this field.