Ba₆(Cu_xZ_y)Sn₄S₁₆ (Z = Mg, Mn, Zn, Cd, In, Bi, Sn): High Chemical Flexibility Resulting in Good Nonlinear-Optical Properties

Abstract

Seven acentric sulfides Ba6(Cu x Z y )­Sn4S16 (Z = Mg, Mn, Zn, Cd, In, Bi, Sn) were grown by a high-temperature salt flux method. The crystal structures of the Ba6(Cu x Z y )­Sn4S16 (Z = Mg, Mn, Zn, Cd, In, Bi, Sn) compounds were determined by single-crystal X-ray diffraction with the aid of solid-state NMR spectroscopy. The Ba6(Cu x Z y )­Sn4S16 (Z = Mg, Mn, Zn, Cd, In, Bi) compounds are isostructural and crystallize in the Ba6Ag4Sn4S16 structure type. The Sn-containing compound exhibits high structural similarity to Ba6(Cu x Z y )­Sn4S16 (Z = Mg, Mn, Zn, Cd, In, Bi) with the presence of an interstitial atomic position partially occupied by Sn atoms. The chemical bonding characteristics of Ba6(Cu2.9Sn0.4)­Sn4S16 were understood with electron localization function calculations coupled with crystal orbital Hamilton population calculations. The Ba–S and Cu–S interactions are dominantly ionic, but the Sn–S interactions consist of strong covalent bonding characteristics in Ba6(Cu2.9Sn0.4)­Sn4S16. The monovalent Cu atoms, mixed with certain metals with various oxidation states, significantly shift the optical properties of the Ba6(Cu x Z y )­Sn4S16 (Z = Mg, Mn, Zn, Cd, In, Bi) compounds. This results in a good balance between the second-harmonic-generation (SHG) response and laser damage threshold (LDT). Ba6(Cu1.9Zn1.1)­Sn4S16 possesses a high SHG response and a high LDT of 2.8 × AGS and 3 × AGS, respectively. A density functional theory calculation revealed that CuS4 and SnS4 tetrahedra significantly contribute to the SHG response in Ba6(Cu2Mg)­Sn4S16, which also confirmed that CuS4 tetrahedra are crucial for the stability and optical properties of the Ba6(Cu x Z y )­Sn4S16 (Z = Mg, Mn, Zn, Cd, In, Bi, Sn) compounds revealed by electronic structure analysis.

Heteroanionic LaBrVIO4 (VI = Mo, W): Excellence in Both Nonlinear Optical Properties and Photoluminescent Properties

“…The small amounts of dysprosium doping also dramatically enhance the SHG response of (La 0.9 Dy 0.1 )­BrWO 4 . Understanding how to enhance SHG in NLO materials is critical for pushing this field forward. − In addition to the SHG response, LaBrWO 4 also possesses better PL properties than LaBrMoO 4 (vide infra). Our further analysis confirms that the distorted 1D [VIO 5 ] VI = Mo,W strands play a critical role in determining the optical properties of LaBrVIO 4 (VI = Mo and W) (vide infra).…”

d6versus d10, Which Is Better for Second Harmonic Generation Susceptibility? A Case Study of K2TGe3Ch8 (T = Fe, Cd; Ch = S, Se)

“…The Ge–S bond distances in K 2 CdGe 3 S 8 fall into the range of 2.160(1)–2.261(1) Å, which are comparable to many germanium-sulfides such as K 2 FeGe 3 S 8 (2.181–2.239 Å), KBiGeS 4 (2.181–2.239 Å), Cs 4 GeP 4 S 12 (2.209–2.232 Å), K 2 ZnGe 3 S 8 (2.148–2.285 Å), KLaGeS 4 (2.175–2.220 Å), K 2 MnGe 3 S 8 (2.125–2.288 Å), Na 5 AgGe 2 S 7 (2.189–2.247 Å), La 4 Ge 3 S 12 [2.196(7)–2.241(7) Å], Ba 6 (Cu 1.9 Mg 1.1 )­Ge 4 S 16 [2.174(8)–2.227(5) Å], and so forth. The Cd–S bond distances within [CdS 4 ] tetrahedra of K 2 CdGe 3 S 8 are 2.486(5)–2.537(5) Å, which agree well with many cadmium-sulfides such as KCd 4 Ga 5 S 12 (2.335–2.429 Å), , K 2 AuCdS 4 (2.597 Å), K 2 Cd 3 S 4 (2.473–2.640 Å), and so forth.…”

“…K 2 CdGe 3 Se 8 has a moderate-high LDTs of 3.4(1)× AgGaS 2 . Many factors, such as band gap, absorption coefficient, thermal conductivity, and thermal expansion coefficient, contribute to the LDTs of solids . As summarized in Table S6, many small band gap selenides exhibit high LDTs and high SHG. − K 2 CdGe 3 S 8 is a promising candidate for infrared NLO material, which combines suitable band gap, good stability, high SHG intensity, high LDTs, and type-I phase-matching behavior.…”

Revisiting two thiophosphate compounds constituting d0transition metal HfP2S6and d10transition metal α-Ag4P2S6as multifunctional materials for combining second harmonic generation response and photocurrent response

“…91 NCS-Ag 4 P 2 S 6 crystallizes in P2 1 2 1 2 1 (No. 19) with unit cell parameters of a = 13.901 (7) Å, b = 11.073(6) Å, and c = 6.303(4) Å. 90 The detailed structure comparison between CS-Ag 4 P 2 S 6 and NCS-Ag 4 P 2 S 6 is summarized in Fig.…”

“…After many years of intensive study, few materials, including AgGaS 2 , ZnGeP 2 , and AgGaSe 2 , have been commercialized due to their balanced properties which play an important role in scientific research and industrial applications. 1–29 These commercial materials, AgGaS 2 , ZnGeP 2 , and AgGaSe 2 , are impeded from high energy use due to their intrinsic limitations including low laser damage threshold, double-photon absorption, and non-phase-matching behavior, respectively. 13,30–32 In addition to energy loss, these commercial materials cannot be employed to cover the full range of the infrared spectrum.…”