Hongshan Wang†, Zhenglong Li†, Ran An, Zhenyou Wang, Juanjuan Lu, Guansong Zheng, Zhihua Yang, Yu Chu*, Junjie Li*

Cite this article: Chin. J. Struct. Chem., 2025, 44(12), 100757. DOI: 10.1016/j.cjsc.2025.100757

Publication date: December 1, 2025

Keywords: Diamond-like framework; Nonlinear optical materials; Chalcogenides system; High laser-induced damage threshold; A^I₂Q^VI-Ag₂Q^VI-C^III₂Q^VI3 system

ABSTRACT

Diamond-like AgGaS2 (DL AGS), as the typical infrared nonlinear optical (IR NLO) material, has suffered from its intrinsic drawbacks like narrow band gap (Eg) and low laser-induced damage threshold (LIDT). In this work, by first introducing [NaS8] polyhedral unit into the $$-Ag2QVI-$$ system, a new Ag-based sulfide NaAg3Ga8S14 with diamond-like framework (DLF) has been successfully synthesized via a high-temperature solid-state method in experiment. The compound shows a wide Eg (∼3.0 eV), high LIDT (3.0 × AGS) and moderate phase-matching NLO response (∼0.7 × AGS), effectively balancing the Eg (≥ 3.0 eV) and NLO response (≥ 0.5 × AGS), demonstrating its promise for IR NLO applications. Theoretical calculations elucidate the orbital hybridization between Na 3s, Ag 4d5s and S 3p enhanced the Eg, and the aligned NLO-active units ([AgS4] and [GaS4]) induced moderate NLO response in the compound. These findings not only expand the chemical and structural diversities of Ag-based chalcogenides, but also provide effective strategies for designing DLF functional materials derived from diamond-like structures.

system, a new Ag-based sulfide NaAg3Ga8S14 with diamond-like framework (DLF) has been successfully synthesized via a high-temperature solid-state method in experiment. The compound shows a wide Eg (∼3.0 eV), high LIDT (3.0 × AGS) and moderate phase-matching NLO response (∼0.7 × AGS), effectively balancing the Eg (≥ 3.0 eV) and NLO response (≥ 0.5 × AGS), demonstrating its promise for IR NLO applications. Theoretical calculations elucidate the orbital hybridization between Na 3s, Ag 4d5s and S 3p enhanced the Eg, and the aligned NLO-active units ([AgS4] and [GaS4]) induced moderate NLO response in the compound. These findings not only expand the chemical and structural diversities of Ag-based chalcogenides, but also provide effective strategies for designing DLF functional materials derived from diamond-like structures.$$