0D chiral hybrid indium(III) halides for second harmonic generation.

Chiral metal halides have shown great potential for application in next generation nonlinear optical (NLO) devices owing to their intrinsic non-centrosymmetry. However, the structures and properties of chiral hybrid indium halides have been rarely reported, especially when it comes to second-harmonic generation (SHG) in NLO. In this work, we have synthesized a pair of new zero-dimensional (0D) chiral hybrid indium halides, ( R -MPEA) 6 InCl 9 and ( S -MPEA) 6 InCl 9 , and studied their NLO properties. The as-prepared chiral hybrid indium halides crystallize in non-centrosymmetric P 3 2 21 and P 3 1 21 space groups, respectively. NLO studies show that 0D chiral hybrid indium halide crystals exhibit strong SHG responses with high polarization ratio and high laser damage threshold (LDT). This work enriches the family of chiral hybrid metal halide materials and offers a feasible strategy for the targeted design and synthesis of intrinsically non-centrosymmetric metal halide materials for NLO applications.