Li[LiCs2Cl][Ga3S6]: A Nanoporous Framework of GaS4 Tetrahedra with Excellent Nonlinear Optical Performance

• Published in: Angewandte Chemie International Edition Vol. 59; no. 12; pp. 4856 - 4859
• Main Authors: Liu, Bin‐Wen, Jiang, Xiao‐Ming, Li, Bing‐Xuan, Zeng, Hui‐Yi, Guo, Guo‐Cong
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 16.03.2020
• Edition: International ed. in English
• Subjects: Chalcogenides; Energy gap; IR nonlinear optics; Nonlinear optics; porous structures; Second harmonic generation; Silver gallium sulfide; solid-state reactions; Tetrahedra; Tunnel construction
• DOI: 10.1002/anie.201912416
• ISSN: 1433-7851

A large nonlinear optical (NLO) coefficient and a wide band gap are two crucial but contradictory parameters that are difficult to achieve simultaneously in a single infrared (IR) NLO compound. A salt‐inclusion chalcogenide (SIC), Li[LiCs2Cl][Ga3S6] (1), was prepared that presents a nanosized tunnel framework constructed from monotype chalcogenide tetrahedra. Highly oriented covalent GaS4 tetrahedra in the host lead to a moderate second harmonic generation response (0.7 AgGaS2), and ionic guests effectively broaden the band gap to the widest value (4.18 eV) among all IR NLO chalcogenides, thereby achieving a remarkable balance between NLO efficiency and band gap. The salt‐inclusion chalcogenide Li[LiCs2Cl][Ga3S6] is presented, which features a 3D framework composed of [Ga3S6] nanosized tunnels. Introduction of an ionic guest to the covalent chalcogenide host produces a material with a moderate nonlinear optical (NLO) coefficient and an ultrawide band gap (Eg). These characteristics are promising for the development of infrared (IR) NLO materials.