Na6TlSb4: Synthesis, Structure, and Bonding. An Electron-Rich Salt with a Chain Conformation and a Tl-Tl Bond Length Determined by the Cation
详细信息 查看全文
- 作者：Bin Li ; Lisheng Chi ; and John D. Corbett
- 刊名：Inorganic Chemistry
- 出版年：2003
- 出版时间：May 5, 2003
- 年：2003
- 卷：42
- 期：9
- 页码：3036 - 3042
- 全文大小：325K
- 年卷期：v.42,no.9(May 5, 2003)
- ISSN：1520-510X
文摘
The title compound forms on fusion and annealing of a stoichiometric mixture of the elements. The structure wasdetermined by single-crystal X-ray diffraction methods in the monoclinic space group C2/c, with a = 15.154(3) Å,b = 10.401(2) Å, c = 17.413(4) Å, and 
= 113.57(3)
, Z = 8. Four-membered Tl-Sb1-Sb4-Sb3 rings interlinkedby pairs of Sb2 bridges generate swinglike repeat units [Tl2Sb8] that are further interlinked through external Tl-Tlbonds to form infinite one-dimensional chains. Cations play a major role in the structure. In contrast to the Zintl-phase K6Tl2Sb3 with similar swinglike [Tl4Sb6] repeating units and Tl-Tl interlinkages, Na6TlSb4 has a more compactconformation of the chains and a notably smaller cell volume than expected. The new phase is metallic with twoexcess cations according to empirical electron counting, EHTB band calculations for the anion, and the compound'smeasured resistivities and magnetic susceptibilities. The notably shorter Tl-Tl bond in the present salt (2.954 Å)can be directly attributed to the smaller cation and reduced intercation repulsions across that bond.
= 113.57(3), Z = 8. Four-membered Tl-Sb1-Sb4-Sb3 rings interlinkedby pairs of Sb2 bridges generate swinglike repeat units [Tl2Sb8] that are further interlinked through external Tl-Tlbonds to form infinite one-dimensional chains. Cations play a major role in the structure. In contrast to the Zintl-phase K6Tl2Sb3 with similar swinglike [Tl4Sb6] repeating units and Tl-Tl interlinkages, Na6TlSb4 has a more compactconformation of the chains and a notably smaller cell volume than expected. The new phase is metallic with twoexcess cations according to empirical electron counting, EHTB band calculations for the anion, and the compound'smeasured resistivities and magnetic susceptibilities. The notably shorter Tl-Tl bond in the present salt (2.954 Å)can be directly attributed to the smaller cation and reduced intercation repulsions across that bond.