A simple adduct from tin tetraiodide SnI4 and octasulfur S8, SnI4⋅(S8)2 (1), is obtained employing a facile reaction. The combination of Sn4+ ions with d10 electron configuration, acentric SnI4 tetrahedra, and lone‐pair effects of S8, makes 1 a phase‐matchable infrared NLO crystal with a moderate second‐harmonic generation (SHG) response and a very high laser‐induced damage threshold (LIDT), which is well confirmed by the DFT calculations.

A big challenge for nonlinear optical (NLO) materials is the application in high power lasers, which needs the simultaneous occurrence of large second harmonic generation (SHG) and high laser induced damage threshold (LIDT). Herein we report the preparation of a new Ga2Se3 phase, which shows the SHG intensities of around 2.3 times and the LIDT of around 16.7 times those of AgGaS2 (AGS), respectively. In addition, its IR transparent window ca. 0.59–25 μm is also significantly wider than that of AGS (ca. 0.48–≈11.4 μm). The occurrence of the strong SHG responses and good phase‐matching indicate that the structure of the new Ga2Se3 phase can only be non‐centrosymmetric and have a lower symmetry than the cubic γ‐phase. The observed excellent SHG and phase‐matching properties are consistent with our diffraction experiments and can be well explained by using the orthorhombic models obtained through our high throughput simulations.

The discovery of new types of metal sulfides is attractive because of their rich structures and diverse physical properties. Here, a novel quaternary sulfide, Ba3HgGa2S7 (BHGS), is obtained by a solid-state reaction at 1123 K. It crystallizes in the monoclinic space group P21/c, and its zero-dimensional structure features two seesaw-like HgS2 units and four GaS4 tetrahedra, constructing a unique [Hg2Ga4S14]12– string. BHGS has a wide band gap of 3.64 eV and a large birefringence of 0.09 at 2100 nm. Specifically, BHGS exhibits a remarkable photocurrent response. This work may be extended to a new family of AE3MIIMIII 2Q7 (AE = Mg, Ca, Sr, Ba; MII = Zn, Cd, Hg; MIII = Al, Ga, In; Q = S, Se) chalcogenides.

Oxyhalides possessing the merits of oxides and halides have widely received attention for their comprehensive physical performances, especially as potential nonlinear optical (NLO) crystals. Here, based on conventional strategy for obtaining acentric compounds, a Te 4+ lone-pair cation was introduced into oxyhalides, and one oxyfluoride, HgTeO 2 F(OH), was obtained via a hydrothermal reaction. Crystallized in the polar space group Pca2 1 , the layered structure of HgTeO 2 F(OH) is composed of V-shaped [HgO 2 ] 2− groups and [TeO 2 F(OH)] 2− pyramids, in which the [TeO 2 F(OH)] 2− pyramid first served as the NLO functional motif. Its powder sample exhibits a phase-matchable SHG response of 1.1 × KH 2 PO 4 at 1064 nm, and its birefringence (0.09@1064 nm) is sufficient for phasematchable behavior, which manifests its comprehensive capacity as a promising NLO candidate. Theoretical calculations about electronic structure and optical properties are also carried out, revealing that the Te 4+ lone-pair cation makes the predominant contribution to the SHG effect and synergizes with the [HgO 2 ] 2− groups.

Phosphite materials have aroused widely attention for their diverse open-frameworks and promising magnetic and optical performances. Here, the first barium scandium phosphite, BaSc2(HPO3)4(H2O)2, was obtained via a facile hydrothermal route....