Tsamourtzi Konstantina, Song Jung-Hwan, Bakas Thomas, Freeman Arthur J, Trikalitis Pantelis N, Kanatzidis Mercouri G
Department of Chemistry, University of Crete, Voutes 71003, Heraklion, Greece.
Inorg Chem. 2008 Dec 15;47(24):11920-9. doi: 10.1021/ic801762h.
The reaction of K(2)Sn(2)Q(5) (Q = S, Se, Te) with stoichiometric amounts of alkyl-ammonium bromides R(4)NBr (R = methyl or ethyl) in ethylenediamine (en) afforded the corresponding salts (R(4)N)(4)[Sn(4)Q(10)] (Q = S, Se, Te) in high yield. Although the compound K(2)Sn(2)Te(5) is not known, this reaction is also applicable to solids with a nominal composition "K(2)Sn(2)Te(5)" which in the presence of R(4)NBr in en are quantitatively converted to the salts (R(4)N)(4)[Sn(4)Te(10)] on a multigram scale. These salts contain the molecular adamantane clusters Sn(4)Q(10) and can serve as soluble precursors in simple metathesis reactions with transition metal salts to synthesize the large family of open-framework compounds (Me(4)N)(2)M[Sn(4)Se(10)] (M = Mn(2+), Fe(2+), Co(2+), Zn(2+)). Full structural characterization of these materials as well as their magnetic and optical properties is reported. Depending on the transition metal in (Me(4)N)(2)M[Sn(4)Se(10)], the energy band gaps of these compounds lie in the range of 1.27-2.23 eV. (Me(4)N)(2)Mn[Ge(4)Te(10)] is the first telluride analogue to be reported in this family. This material is a narrow band gap semiconductor with an optical absorption energy of 0.69 eV. Ab initio electronic band structure calculations validate the semiconductor nature of these chalcogenides and indicate a nearly direct band gap.
K₂Sn₂Q₅（Q = S、Se、Te）与化学计量的烷基溴化铵R₄NBr（R = 甲基或乙基）在乙二胺（en）中反应，高产率地得到了相应的盐（R₄N）₄[Sn₄Q₁₀]（Q = S、Se、Te）。尽管化合物K₂Sn₂Te₅尚不存在，但该反应也适用于标称组成为“K₂Sn₂Te₅”的固体，在en中存在R₄NBr的情况下，这些固体能以多克规模定量转化为盐（R₄N）₄[Sn₄Te₁₀]。这些盐包含分子金刚烷簇[Sn₄Q₁₀]⁴⁻，可作为与过渡金属盐进行简单复分解反应的可溶性前体，用于合成大量的开放框架化合物（Me₄N）₂M[Sn₄Se₁₀]（M = Mn²⁺、Fe²⁺、Co²⁺、Zn²⁺）。报道了这些材料的完整结构表征及其磁学和光学性质。根据（Me₄N）₂M[Sn₄Se₁₀]中的过渡金属不同，这些化合物的能带隙在1.27 - 2.23 eV范围内。（Me₄N）₂Mn[Ge₄Te₁₀]是该系列中首个被报道的碲化物类似物。这种材料是一种窄带隙半导体，光吸收能量为0.69 eV。从头算电子能带结构计算验证了这些硫族化物的半导体性质，并表明其为近直接带隙。
