{[In₂S₇]^8–}_∞ Chain and Isolated HgS₄ Planar Unit Constructed One-Dimensional Pentanary Sulfide K₂Ba₇HgIn₄S₁₆ Exhibiting Nonlinear-Optical Activity

Abstract

Hg-based chalcogenides possess diverse structures, large nonlinear-optical (NLO) responses, and suitable birefringences, making them potentially suitable for numerous crucial criteria of practical application as infrared (IR) NLO crystals. Here, a new pentanary Hg-based sulfide K2Ba7HgIn4S16 has been discovered by a high-temperature solid-state method. It crystallizes in the orthorhombic P21212 space group, and its one-dimensional structure is constructed by {[In2S7]8–}∞ chains and isolated [HgS4]6– planar quadrilateral units located bewteeen the chains, representing a novel type of chalcogenide. K2Ba7HgIn4S16 exhibits a moderate NLO effect of 0.5 × AGS at 2.1 μm and a high laser-induced damage threshold of ∼5.8 × AGS, as well as a band gap of 2.98 eV, demonstrating that K2Ba7HgIn4S16 is a potential IR NLO material. This work enriches the structural chemistry of chalcogenides and the family of Hg-based IR NLO chalcogenides.

KHg4Ga3S9: A Hg-Based Sulfide with Nonlinear-Optical Activity in the A–MII–MIII–Q (A = Alkali Metal; MII = d10 Metal; MIII = Ga, In; Q = S, Se) System

“…(3) d 10 cations (Zn 2+ , Cd 2+ , and Hg 2+ ) are favorable for large birefringence . Several Hg-based chalcogenides are reported as IR NLO candidates, like Na 2 Hg 3 M 2 S 8 (M = Si, Ge, Sn), AEHgGeSe 4 (AE = Ba, Sr), K 2 Ba 7 HgIn 4 S 16 , and Li 2 HgMS 4 (M = Si, Ge, Sn) …”

A2Hgx(SeO3)y (A = K, Rb, Cs): Three Alkali Metal Mercury Selenites Featuring Unique 1D [HgOm(SeO3)n]∞ Chains

“…Herein, the d 10 transition metal cation Hg 2+ was considered to be the ideal cation structural units to design new selenite. Hg 2+ cations with various coordination environments can produce diverse distorted polyhedra, such as linear, plane triangle, tetrahedron, octahedron, bipyramid model, which further contribute to structural diversification of crystal. − Moreover, Hg 2+ cations have a larger deformation rate and polarizability compared to Zn 2+ and Cd 2+ , despite having similar electronic structures. This characteristic effectively increases the second harmonic generates response and birefringence, as confirmed by LiHgPO 4 , Hg 3 O 2 SO 4 , CsHgNO 3 Cl 2 , and so on.…”

EuSi7P10: An Inorganic Supramolecular Nonlinear Optical Crystal Exhibiting Strong Second-Harmonic Generation Response

“…Second-order nonlinear optical (NLO) materials hold significant relevance for laser communication and optoelectronic devices, owing to their utility as innovative laser sources for frequency conversion. − In particular, mid-infrared (mid-IR, 3–25 μm) NLO materials play an important role in signal communication, noninvasive medical diagnostics, and laser guidance. − At present, commercially available IR NLO materials are predominantly composed of chalcopyrite-type compounds, including AgGaS 2 (AGS), AgGaSe 2 (AGSe), and ZnGeP 2 (ZGP). − These materials are noted for their substantial second-harmonic generation (SHG) responses and broad IR transparency. However, they possess inherent disadvantages such as a low laser damage threshold (LDT) and two-photon absorption (TPA), which significantly impede their further utilization in high-power lasers.…”