M6PS5X (M = Ag, Cu; X = Cl, Br) chalcohalides exhibiting strong nonlinear optical responses and high laser damage resistances

A series of M6PS5X (M = Ag, Cu; X = Cl, Br) nonlinear optical (NLO) chalcohalides with the special MS3X ligands were synthesized in this work. Their critical optical performances were systematically measured and the research result shows that all of them exhibit the strong NLO responses (2.0-2.7 × commerical AgGaS2) and high laser-damage thresholds (1.7-2.3 × AgGaS2), indicating their potential application as good NLO candidates. Furthermore, first-principles calculation was used to study their inherent structure-property relationship and chalcohalides can be expected as one optimal system on exploration of new promising IR NLO crystals.