Al Flux Synthesis of the Oxidation-Resistant Quaternary Phase REFe4Al9Si6 (RE = Tb, Er)
Al Flux Synthesis of the Oxidation-Resistant Quaternary Phase REFe4Al9Si6 (RE = Tb, Er)
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DOI：
10.1021/cm801554d
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发表时间：
2008-10
影响因子：
8.6
通讯作者：
B. Sieve;Danielle L. Gray;R. Henning;T. Bakas;A. Schultz;M. Kanatzidis
中科院分区：
文献类型：
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作者：
B. Sieve;Danielle L. Gray;R. Henning;T. Bakas;A. Schultz;M. Kanatzidis
Two rare earth iron aluminum silicides, REFe4Al9Si6 (RE = Tb, Er), were synthesized in liquid Al at temperatures below 850 °C. They crystallize in the tetragonal space group P42/nmc (no. 137) with cell dimensions of a = 8.718(1) A and c = 15.171(3) A for the Tb analogue. The structure, which is highly intricate and represents a rare structural arrangement, is based on that of NdRh4Al15.4. It can be understood in terms of highly corrugated layers of merged Al6 rings stacking to form a three-dimensional framework. The Fe and Si atoms are situated in various sites in the framework. The RE atoms have a very high coordination number (20) and sit in remaining pockets formed by the bonding arrangements in the structure. Magnetic measurements show that the rare earth ions are in a 3+ state, whereas Mossbauer measurements show that the Fe atoms do not exhibit a magnetic moment and are more reduced than in elemental Fe. The possible insights gained from these results into the metallurgical processing of advanced al...
