Achiral Fluorinated Aromatic Ligands Based Chiral Hybrid Antimony Halides with High-Efficiency Second-Harmonic Generation

Hybrid organic-inorganic metal halides (HOMHs) have emerged as an ideal platform for the construction of semiconductor materials with promising optoelectronic properties. A number of HOMHs based on different metals including Sb3+ have been demonstrated with second-harmonic generation (SHG) properties, but their nonlinear optical (NLO) performances including effective conversion wavelength range, optical stability, and NLO coefficients are not yet satisfactory. Here, by adopting a molecular design involving fluorine-substitution on the achiral organic ammonium, this work has synthesized single crystals of two new chiral noncentrosymmetric HOMHs, (2-FPEA)(2)SbX5 (X = Cl and Br), with large polarization ratios and outstanding optical transparency. The second-order NLO coefficients of (2-FPEA)(2)SbCl5 and (2-FPEA)(2)SbBr5 are determined to be & AP;24.3 and 21.6 pm V-1. Significantly, the Sb3+-based HOMHs enable very high thermal stability and laser resistance. The distinguished laser-induced damage thresholds (LDTs) have been estimated to be as high as 3.44 mJ cm(-2) for (2-FPEA)(2)SbCl5 and 3.32 mJ cm(-2) for (2-FPEA)(2)SbBr5, higher than that of the reported HOMHs. Such a highly efficient SHG performance and stability indicate the promising future of these Sb3+-based metal halides for nonlinear photonic applications.

Automated summary

In this study, two new chiral noncentrosymmetric hybrid organic-inorganic metal halide crystals, (2-FPEA)(2)SbCl5 and (2-FPEA)(2)SbBr5, were synthesized with large polarization ratios and outstanding optical transparency. Their second-order nonlinear optical coefficients were determined to be 24.3 and 21.6 pm V-1, respectively. Furthermore, these Sb3+-based metal halides exhibited high thermal stability and laser resistance, with laser-induced damage thresholds higher than previously reported hybrid organic-inorganic metal halides. These findings indicate the promising future of Sb3+-based metal halides for nonlinear photonic applications.