Synthesis and Structure of Cs₂[As(CH₃)Se₃] · 2H₂O and Cs₂As₄Se₆ containing the Catena‐hexaselenidotetraarsenate(II, III) Anion $^{1}_{\infty}\rm [As_{4}Se_{6}^{\phantom{\infty}2-}]$

Abstract

Heating CsAsSe3 · 0.5H2O in methanol to 190 °C leads to formation of black Cs2As4Se6 (1) together with red Cs4As4Se8 and a colourless solution from which the substituted caesium selenidoarsenates(V) Cs2[As(CH3)Se3] · 2H2O (2) and Cs[As(CH3)2Se2] can be obtained as crystalline fractions. Cs2As4Se6 contains catena‐hexaselenidotetraarsenate(II,III) anions in which cyclic As3Se5 units are linked through corner‐sharing AsSe3 pyramids into infinite chains $^{1}_{\infty}\rm [As_{4}Se_{6}^{\phantom{\infty}2-}]$. The Cs symmetric As3Se2 five‐membered rings of the As3Se5 units display an envelope conformation with an As‐As bond length 2.528(3) Å and As‐Se distances of 2.449(2) and 2.447(2) Å. Cs symmetry is also observed for the discrete tetrahedral [As(CH3)Se3]2− anions of (2).

Solvothermal syntheses, and characterization of [Ln(en)4(SbSe4)] (Ln=Ce, Pr) and [Ln(en)4]SbSe4·0.5en (Ln=Eu, Gd, Er, Tm, Yb): The effect of lanthanide contraction on the crystal structures of lanthanide selenidoantimonates(V)

“…The molecular structure of 1a is depicted in Fig. 1 [27]. To the best of our knowledge, the compounds 1a-1d are the only examples of selenidoantimonate(V) compounds in which the SbSe 4 3À anion acts as ligands to lanthanide(III) centers in amine solutions.…”

“…3À anion can act as a bidentate ligand to bridge transition metal complexes, such as [Mn(en) 2 (m-SbSe 4 )] À and [{Mn(en) 2 (H 2 O)} 2 (m-SbSe 4 )] + fragments in compound [Mn(en) 3 ][Mn 2 (en) 4 (-H 2 O) 2 (m-SbSe 4 )][Mn(en) 2 (m-SbSe 4 )]Cl 2[27]. In addition, the coordination mode of SbSe 4 3À is also different from that of analogous…”

Five dimeric thiogermanates with transition metal complexes of multidentate chelating amines: Syntheses, structures, magnetism and photoluminescence

“…Different roles of L n -dentate (n = 2-5) chelating amines on the construction of hybrid main-group metal chalcogenides It has been demonstrated that the self-assembly directed by unsaturated TMCs is an effective strategy for the construction of metal chalcogenides incorporated with TMCs [17]. Generally, L 2 and L 3 -dentate chelating amines are preferable to coordinate to TM ion to form saturated [TM(L 2 ) 3 ] n+ or [TM(L 3 ) 2 ] n+ complex cations, which prevents the TM amine complexes from bonding with metal chalcogenides to form new inorganic-organic hybrid chalcogenides incorporated with TMCs, although several examples are obtained under certain reaction condition [18,26,29,[55][56][57][58][59]. Alternatively, L 4 and L 5 -dentate chelating amines usually coordinate to TM ions to form unsaturated TMCs, which can effectively incorporate into metal chalcogenide frameworks to form novel hybrid chalcogenides with diverse structures.…”

Review. Solvothermal Synthesis and Structure of Chalcogenidoarsenate Anions

“…The metal atoms of such cations can be connected with the terminal chalcogens of oligomeric or polymeric anions to prevent their further propagation or can be directly incorporated into anionic or neutral networks when two or more free coordination sites are available in the fragment. For instance, the 1D polymer 1 ∞ [{Mn(tren)}(As 4 [14] and Cs 4 BiAs 3 Se 7 [15] and the isolation of novel binary lower oxidation state selenidoarsenates such as the 1 ∞ [As 4 Se 6 2− ] chain anions of Cs 2 As 4 Se 6 [16], which contain both As(II) and As(III) atoms.…”