Syntheses and characterization of three new sulfides with large band gaps: acentric Ba₄Ga₄SnS₁₂, centric Ba₁₂Sn₄S₂₃ and Ba₇Sn₃S₁₃

Abstract

The desirable development of infrared nonlinear optical (IR NLO) materials is to design new compounds which exhibit wide band gaps and strong second harmonic generation (SHG) responses. Herein, we report three new sulfides, BaGaSnS (1), BaSnS (2) and BaSnS (3), with wide band gaps of 2.90, 2.98 and 3.0 eV, respectively, which have been successfully synthesized for the first time. Significantly, compound 1 exhibited a large SHG coefficient (34 × KDP), illustrating a good balance between the band gap and the SHG response. Single crystal X-ray diffraction determined that compound 1 crystallizes in the non-centrosymmetric space group P4[combining macron]2c and it was characterized as an interesting kite-shaped linkage motif of [GaSnS]. Compounds 2 and 3 crystallize in the space groups of P2c and Pnma, respectively. In addition, compounds 2 and 3 were characterized as zero-dimensional (0D) structures comprising isolated SnS tetrahedra with Ba cations and S anions located between them. However, compound 2 contains extra disulfide S anions in its isolated structure. Moreover, the theoretical calculations demonstrated that SHG responses for compound 1 could be ascribed to the transitions from S-3p and Ga-4p states to Ba-5d, Ga-4p and Sn-5p states. By analysing the relationship between the structures and properties for PbGaGeS-type compounds, it was concluded that site disorder could be an effective way to improve optical properties.

Effect of Element Substitution on Structural Transformation and Optical Performances in I2BaMIVQ4 (I = Li, Na, Cu, and Ag; MIV = Si, Ge, and Sn; Q = S and Se)

“…Exploration of a new family of compounds is important to enrich the structural chemistry. − Recently, increasing attention has been focused on metal chalcogenides because of their diverse structural chemistry and excellent performances. − In review of the structural features for known chalcogenides, they commonly possess the same structures by the substitution of the same main group elements, for example, LiGaS 2 vs LiInS 2 (orthorhombic, Pna 2 1 ), AgGaS 2 vs AgGaSe 2 (tetragonal, I 4̅2 m ), and Li 2 BaGeS 4 vs Li 2 BaSnS 4 (tetragonal, I 4̅2 m ), etc. However, it should be noted that obvious structural transformations have also occurred with the replacement of different alkali or alkaline earth metals in the crystal structures, such as Ba 2 GeSe 4 ( P 2 1 / m ) vs Mg 2 GeSe 4 ( Pnma ) and Li 2 CdSnS 4 ( Pmn 2 1 ) vs Na 2 CdSnS 4 ( C 2).…”

Directed Dehydration as Synthetic Tool for Generation of a New Na4SnS4 Polymorph: Crystal Structure, Na+ Conductivity, and Influence of Sb‐Substitution

“…In addition, Sn occurs mainly in the oxidation state IV, but compounds with different oxidation states like II/IV or III/IV were also reported [10–12] . Thiostannates with metal cations as counter ions were mainly synthesized using the molten‐flux approach, [13, 14] or via high‐temperature syntheses [15–19] . Thiostannates with protonated amine molecules, transition metal cations, or transition metal complexes as counter ions compensating the negative charge of the [Sn x S y ] n − anions were mostly prepared under solvothermal conditions [9, 20–35] .…”

“…[10][11][12] Thiostannates with metal cations as counter ions were mainly synthesized using the molten-flux approach, [13,14] or via high-temperature syntheses. [15][16][17][18][19] Thiostannates with protonated amine molecules, transition metal cations, or transition metal complexes as counter ions compensating the negative charge of the [Sn x S y ] nÀ anions were mostly prepared under solvothermal conditions. [9,[20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] Applying suitable precursors, the preparation of thiostannates at room temperature was also reported.…”

The synthesis and structure–property relation analysis of metal chalcohalide crystals Cs2InPS4X2 (X = Cl, Br) with mixed anions

“…17 Metal chalcogenides with low bandgaps are widely implemented in solar cells and wide bandgap materials are transparent in infrared region, which is especially fit for infrared optics. [18][19][20][21][22] In this regard, the exploration of new metal chalcohalides with unique structures and properties is considerably significant.…”