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Metal chalcogenophosphates are receiving increasing interest, specifically as promising infrared nonlinear optical (NLO) candidates. Here, a rare‐earth chalcogenophosphate Eu2P2S6 crystallizing in the monoclinic noncentrosymmetric space group Pn was synthesized using a high‐temperature solid‐state method. Its structure features isolated [P2S6]4− dimer, and two types of EuS8 bicapped triangular prisms. Eu2P2S6 exhibits a phase‐matchable second‐harmonic generation (SHG) response ≈0.9×AgGaS2@2.1 μm, and high laser‐induced damage threshold of 3.4×AgGaS2, representing the first rare‐earth NLO chalcogenophosphate. The theoretical calculation result suggests that the SHG response is ascribed to the synergetic contribution of [P2S6]4− dimers and EuS8 bicapped triangular prisms. This work provides not only a promising high‐performance infrared NLO material, but also opens the avenue for exploring rare‐earth chalcogenophosphates as potential IR NLO materials. [ABSTRACT FROM AUTHOR]

Infrared nonlinear optical (IR NLO) materials are significant in laser technology for civil and military uses. Here, we report the synthesis, structural chemistry and NLO properties of a halogen‐rich chalcohalide Sn7Br10S2. Its noncentrosymmetric (NCS, P63) structure can be considered as partially aliovalent anion substitution of SnBr2 (P63/m) induced centrosymmetric (CS) to NCS structural transformation. The 3D∞[Sn(1)6Sn(2)6Br6X6]6− (X=Br/S) channel framework consists of Sn(1)BrX2 and Sn(2)X3 trigonal pyramids. It exhibits excellent NLO performance, including a strong phase‐matchable NLO response of 1.5 × AgGaS2and high laser‐induced damage threshold of 6.3 × AgGaS2.Investigation of the structure–NLO performance relationship confirms that the effective arrangement of Sn(1)BrX2 and Sn(2)X3 units predominantly contributes to the large SHG response. These results indicate Sn7Br10S2 is a potential IR NLO candidate and provides a new feasible system for promising NLO materials. [ABSTRACT FROM AUTHOR]

Abstract: 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. [ABSTRACT FROM AUTHOR]

Leucosceptroids A and B are sesterterpenoids with potent antifeedant and antifungal activities. A more efficient gram-scale total synthesis of leucosceptroid B and the first total synthesis of leucosceptroid A are presented. The key transformations include an aldol reaction between a substituted dihydrofuranone and an ( S)-citronellal-derived aldehyde, a SmI2-mediated intramolecular ketyl-olefin radical cyclization, and final-stage alcohol oxidation. [ABSTRACT FROM AUTHOR]