Quaternary Germanides RE4Mn2InGe4 (RE = La鈥揘d, Sm, Gd鈥揟m, Lu)

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• 作者：Anton O. Oliynyk ; Stanislav S. Stoyko ; Arthur Mar
• 刊名：Inorganic Chemistry
• 出版年：2013
• 出版时间：July 15, 2013
• 年：2013
• 卷：52
• 期：14
• 页码：8264-8271
• 全文大小：506K
• 年卷期：v.52,no.14(July 15, 2013)
• ISSN：1520-510X

文摘

The quaternary germanides RE₄Mn₂InGe₄ (RE = La鈥揘d, Sm, Gd鈥揟m, Lu) have been prepared by arc-melting reactions of the elements and annealing at 800 掳C and represent the second example of the RE₄M₂InGe₄ series previously known only for M = Ni. Single-crystal X-ray diffraction studies conducted on the earlier RE members of RE₄Mn₂InGe₄ confirmed that they adopt the monoclinic Ho₄Ni₂InGe₄-type structure [space group C2/m, a = 16.646(2)鈥?5.9808(9) 脜, b = 4.4190(6)鈥?.2363(2) 脜, c = 7.4834(10)鈥?.1590(4) 脜, 尾 = 106.893(2)鈥?06.304(1)掳 in the progression of RE from La to Gd]. The covalent framework contains Mn-centered tetrahedra and Ge₂ dimers that build up [Mn₂Ge₄] layers, which are held weakly together by four-coordinate In atoms and outline tunnels filled by the RE atoms. This bonding picture is supported by band-structure calculations. An alternative description based on Ge-centered trigonal prisms reveals that RE₄Mn₂InGe₄ is closely related to RE₂InGe₂. The electrical resistivity behavior of Pr₄Mn₂InGe₄ is similar to that of Pr₂InGe₂.