On the Crystal Structure of the Germanium-Based Cationic Clathrates [Ge38.3Sb7.7]I-7.44, [Ge38.1P7.9]I-8, and [Ge30.5Sn7.7P7.75]I-7.88

作者:Kirsanova M A*; Reshetova L N; Olenev A V; Shevelkov A V
来源:Russian Journal of Coordination Chemistry, 2012, 38(3): 192-199.
DOI:10.1134/S1070328412030062

摘要

Compounds [Ge38.3Sb7.7]I-7.44, [Ge38.1P7.9]I-8, and [Ge30.5Sn7.7P7.75]I-7.88 with the clathrate type-I Lstructure were synthesized. They crystallize in the cubic space group Pm (3) over barn with the unit cell parameter a = 10.8592(9), 10.4983(12), and 10.7210(10) angstrom (Z = 1), respectively. Their crystal structure represents the germanium(tin)-pnictogen framework, capturing the guest iodine anions in its cavities. All compounds have no vacancies in the host substructure; however, two of them show vacancies in the guest positions. The atomic distribution over the framework sites is of the most interest as it follows trends associated with the relative electronegativities of the atoms composing the framework. The results of the band structure calculations and application of the Zintl counting scheme are also discussed in relation to potential thermoelectric properties.

  • 出版日期2012-3