Sn₇Br₁₀S₂: The First Ternary Halogen‐Rich Chalcohalide Exhibiting a Chiral Structure and Pronounced Nonlinear Optical Properties

Abstract

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 Sn 7 Br 10 S 2 . Its noncentrosymmetric (NCS, P6 3 ) structure can be considered as partially aliovalent anion substitution of SnBr 2 (P6 3 /m) induced centrosymmetric (CS) to NCS structural transformation. The 3D 1 [Sn(1) 6 Sn(2) 6 Br 6 X 6 ] 6À (X = Br/S) channel framework consists of Sn(1)BrX 2 and Sn(2)X 3 trigonal pyramids. It exhibits excellent NLO performance, including a strong phase-matchable NLO response of 1.5 × AgGaS 2 and high laser-induced damage threshold of 6.3 × Ag-GaS 2 .Investigation of the structure-NLO performance relationship confirms that the effective arrangement of Sn(1)BrX 2 and Sn(2)X 3 units predominantly contributes to the large SHG response. These results indicate Sn 7 Br 10 S 2 is a potential IR NLO candidate and provides a new feasible system for promising NLO materials.

AAg2PS4(A = K, Na/K): the first-type of noncentrosymmetric alkali metal Ag-based thiophosphates exhibiting excellent second-order nonlinear optical performances

“…45 The LIDT values were calculated from the equation: I (threshold) = E/(πr 2 τ p ), where E, r, and τ p represent the energy of a single pulse, the spot radius, and the pulse width, respectively. 19…”

“…Unfortunately, all of them suffer from intrinsic weaknesses like low laser-induced damage thresholds (LIDTs). [17][18][19] Accordingly, it is urgently necessary, while challenging, to discover new high-performance MIR NLO crystals.A state-of-the-art IR NLO crystal should achieve several key conditions concurrently, such as the noncentrosymmetric (NCS) structure that is the prerequisite for a material to be NLO-active, a large SHG coefficient (d ij > 0.5 × AGS), a high LIDT, suitable birefringence (Δn) (0.03-0.10) for phase-matching (PM), and a wide band gap for wide transmission range (E g > 3.0 eV), together with low melting point and good physicochemical properties for bulk crystal growth. 20,21 However, it is still difficult to develop a NLO crystal with a balance between the above qualifications because of the inverse relationship of the SHG response and the LIDT intensity with the structrure.…”

“…Unfortunately, all of them suffer from intrinsic weaknesses like low laser-induced damage thresholds (LIDTs). [17][18][19] Accordingly, it is urgently necessary, while challenging, to discover new high-performance MIR NLO crystals.…”

Tuning the nonlinear susceptibility and linear parameters upon annealing Ag60−xSe40Texnanostructured films for nonlinear and photonic applications

“…Several chalcogenide-based crystals are used to produce larger nonlinear optic with good efficiency [75] . Other halogen-rich chalcogen material shows pronounced non-linear optical behavior due to its chiral property [76] . These materials are also used for the infrared nonlinear optical applications and mostly produce high-performance nonlinear optics.…”

Halogen regulation triggers structural transformation from centrosymmetric to noncentrosymmetric switches in tin phosphate halides Sn2PO4X (X = F, Cl)

“…31,32 In fact, Sn 2+ is not only the birefringenceactive unit, but also the NLO-active unit. [33][34][35][36] The distorted polyhedra constructed by Sn 2+ usually exhibit large polarizability, which is beneficial for generating a large SHG response. However, regrettably, the overwhelming majority of the reported Sn 2+ -based crystals crystallized in centrosymmetric (CS) space groups.…”