Supercubooctahedron (Cs₆Cl)₂Cs₅[Ga₁₅Ge₉Se₄₈] Exhibiting Both Cation and Anion Exchange

Abstract

A novel type of supertetrahedral connectivity is exhibited by the 72-atom discrete supercubooctahedron in (Cs6Cl)2Cs5[Ga15Ge9Se48] (1), which undergoes both cation and anion exchange, as revealed by unambiguous single-crystal X-ray diffraction data. Electronic-structure studies helped to understand the Ge/Ga distribution.

Six New Members of the A2MIIMIV3Q8 Family and Their Structural Relationship

“…The bond distances of 3.42–4.18, 2.15–2.27, 3.58–4.12, 2.29–2.42, and 2.45–2.58 Å are corresponding to the Cs–S, Ge–S, Cs–Se, Ge–Se, and Sn–Se bonds, respectively, which are consistent with those in the Cs 2 M II M IV 3 Q 8 family . The bond distances 3.36–3.86, 2.40–2.44, 3.44–4.09, and 2.52–2.60 Å of Rb–S, Mn–S, Rb–Se, and Mn–Se bonds, respectively, are comparable with those of Rb 2 Hg 3 Sn 2 S 8 (3.28–3.88 Å), Li 4 MnGe 2 S 7 (2.40–2.46 Å), (RbCl) 2 Cs 5 (Ga 15 Ge 9 Se 48 ) (3.49–3.99 Å), and CsGdMnSe 3 (2.50–2.59 Å) …”

(Cs6Cl)6Cs3[Ga53Se96]: A Unique Long Period-Stacking Structure of Layers Made from Ga2Se6 Dimers via Cis or Trans Intralayer Linking

“…According to diffuse reflectance at room temperature, the band gap of (Cs 6 Cl) 6 Cs 3 [Ga 53 Se 96 ] is estimated to be 2.74 eV (Figure ), which is in agreement with its light-yellow color and suggests semiconductor behavior. This value is smaller than those of Ba 3 AGa 5 Se 10 Cl 2 (A = K–Cs; 3.22–3.25 eV), Ba 4 MGa 4 Se 10 Cl 2 (M= Zn, Cd; 2.93–3.08 eV), and (Cs 6 Cl) 2 Cs 5 [Ga 15 Ge 9 Se 48 ] (2.91 eV), but wider than those of Ba 3 GaSe 4 Cl (2.05 eV) and binary Ga 2 Se 3 (1.88 eV) . It is clear that the introduction of AX alkali-metal halides into MQ n chalcogenides can effectively increase the band gap.…”

“…Also, some show rich structural chemistry and fascinating physical properties. For instance, (Cs 6 Cl) 2 Cs 5 [Ga 15 Ge 9 Se 48 ], an unusual supercubooctahedron, exhibits both cation- and anion-exchange properties . (K 3 I)­[SmB 12 (GaS 4 ) 3 ], a chiral honeycomb-like open framework, exhibits moderate second harmonic generation (SHG) .…”

Tunable Salt-Inclusion Chalcogenides for Ion Exchange, Photoluminescence, and Scintillation

“…Multiple parameters affect the formation of SICs, e.g., the halide salt, the framework building block, the temperature profile, and the choice of flux. To better understand the formation of Ga Q 4 -based SICs, we analyzed the 39 reported Ga Q 4 -based frameworks. − ,,,,,,− The data in Tables S10 and S11 reveal that polychalcogenide flux crystal growth can be successfully coupled with halide fluxes to obtain single crystals of SICs. The polychalcogenide flux, over a wide range of temperatures, appears to increase the solubility and reactivity of the chalcogenide reagents and intermediates, consistent with hard-soft principles .…”

“…Those findings are in line with the literature. Wu and coworkers attempted to carry out the anion exchange of Cl – to F – in [Cs 6 Cl] 2 Cs 5 Ga 15 Ge 9 Se 48 using a KF/CsF mixture at 630 °C for 60 h of dwelling time; however, the tube was corroded, and no crystals were found . Therefore, we believe that a significant reduction of F – concentration in the flux by adding CsI to CsF salt and using the crimped silver tube guided the successful exchange reaction.…”