Intermetallic Compounds with Near Zintl Phase Behavior: RE2Zn3Ge6 (RE = La, Ce, Pr, Nd) Grown from Liquid Indium

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• 作者：James R. Salvador ; Daniel Bilc ; Jeffrey R. Gour ; Subhendra D. Mahanti ; and Mercouri G. Kanatzidis
• 刊名：Inorganic Chemistry
• 出版年：2005
• 出版时间：November 28, 2005
• 年：2005
• 卷：44
• 期：24
• 页码：8670 - 8679
• 全文大小：347K
• 年卷期：v.44,no.24(November 28, 2005)
• ISSN：1520-510X

文摘

A series of compounds has been discovered while investigating reactions of rare earth, transition metals, and Gein excess indium. These compounds, RE₂Zn₃Ge₆ (RE = La, Ce, Pr, Nd), are isostructural, crystallizing in theorthorhombic space group Cmcm with lattice parameters a = 5.9691(9) Å, b = 24.987(4) Å, and c = 5.9575(9)Å for La₂Zn₃Ge₆, a = 5.9503(5) Å, b = 24.761(2) Å, and c = 5.9477(5) Å for the Ce analogue, a =5.938(2) Å,b = 24.708(8) Å, and c = 5.936(2) Å for Pr₂Zn₃Ge₆, and a = 5.9094(7) Å, b = 24.619(3) Å, and c = 5.9063(5)Å for the Nd analogue. The structure is composed of PbO-like ZnGe layers and ZnGe₄ cage layers and is relatedto the Ce₄Zn₈Ge_11-x structure type. The bonding in the system can be rationalized using the Zintl concept resultingin a material that is expected to be a valence precise semiconductor, although its behavior is more consistent withit being a semimetal, making it an intermediate case. The results of band structure calculations and magneticmeasurements of these compounds are discussed.