Reactive flux syntheses, crystal structures and band gaps of AInS2 (A=Rb, Cs)

Unusual Atmospheric Water Trapping and Water Induced Reversible Restacking of 2D Gallium Sulfide Layers in NaGaS2 Formed by Supertetrahedral Building Unit

“…This supports conclusions reached from diffuse reflectance measurements (Figure ) that the gap is about 4.0 eV. A similar agreement between hybrid functional (HSE) predictions and the experiment was observed in the case of A InS 2 ( A = K, Rb, and Cs), materials with the same structure type. , …”

“…NaGaS 2 ( 1 ) and NaFe 0.135 Ga 0.865 S 2 ( 2 ) crystallize in the C 2/ c space group in a very well-known TlGaSe 2 structure type, in which a large number of materials with the ATQ 2 ( A = alkali metal or Tl, T = a triel element except B, and Q = chalcogen) composition have been reported. − These include ATQ 2 ( A = K, Rb, and Cs; T = Ga and In; Q = S, Se); − ,− Tl TQ 2 ( T = Al, Ga, In; Q = S, Se), NaAlSe 2 , and KAlTe 2 . The asymmetric unit of the structures contains two Ga, two Na, and five S crystallographically independent atoms (Figure a).…”

“…However, synthesis of predesigned materials with molecular building units is often challenging albeit possible following an intuitive chemical synthesis route. One such well-known building unit is the super-tetrahedral T2 building unit and connectivities between the T2 building units lead to layers interleaved by charge compensating alkali ions, for example, in ATQ 2 ( A = K, Cs, Rb, Tl; T = Triel element, Q = chalcogen) − series of materials crystallizing in TlGaSe 2 structure type . Among the various compositions in this structure type, TlGaQ 2 is the most studied material due to its dielectric, optical, and radiation detection properties. − Despite extensive investigations, a Na analogue of A Ga Q 2 was missing except for a predicted one with a pyrite structure .…”

Structural, elastic, electronic and optical properties of KAl Q 2 ( Q = Se, Te): A DFT study

“…Theoretical investigation of the electronic properties of the KGaQ 2 crystals has been also performed by Feng et al [1]. In contrast, there is very limited information on the physical properties of KAlQ 2 .The X-ray powder data have been reported in literature [8], showing that KAlSe 2 and KAlTe 2 are isostructural with KGaSe 2 , RbInQ 2 (Q ¼ S, Se), TlGaSe 2 , KInS 2 , KInSe 2 , and AInS 2 (A ¼ Rb, Cs) layered structures [1,10,11] . Therefore, the main objective of the present work is to explore in more detail the structural, elastic, electronic and optical properties of KAlTe 2 and KAlSe 2 crystals using first principles calculations in the framework of the density functional theory.…”

New Lithium‐Containing Pnictides with 1‐D Infinite Chains of Supertetrahedral Clusters: Synthesis, Crystal and Electronic Structure of Ba4Li2Cd3Pn6 (Pn = P, As and Sb)

“…Such atomic packing with T2 cluster makes these materials to be structurally related to a family of supertetrahedra‐layered compounds including mostly indium or gallium sulfides, selenides and tellurides. Some representative examples are CsInSe 2 /CsInTe 2 ,24,25 RbInS 2 ,26 and TlGaSe 2 ,27 among the about 25 known compounds,28 which all crystallize in the monoclinic space group C 2/ c . The present work represents a rare case and the first instance of ordered quaternary pnictides built upon [Cd 4 Pn 10 ] adamantane‐like clusters assembled into infinite chains.…”