Novel Intermetallic Compound UFe5Si3: A New Room-Temperature Magnet with an Original Atomic Arrangement

详细信息    查看全文

• 作者：David Berthebaud ; Antonio P. Gonç ; alves ; Olivier Tougait ; Michel Potel ; Elsa B. Lopes ; Henri Noë ; l
• 刊名：Chemistry of Materials
• 出版年：2007
• 出版时间：July 10, 2007
• 年：2007
• 卷：19
• 期：14
• 页码：3441 - 3447
• 全文大小：277K
• 年卷期：v.19,no.14(July 10, 2007)
• ISSN：1520-5002

文摘

The new compound UFe₅Si₃ was prepared by rapid solidification of the melt using a splat coolingtechnique, followed by annealing at 1173 K for 10 days. Its crystal structure was determined ab initiofrom powder X-ray diffraction data. It crystallizes in the tetragonal space group P4/mmm, with latticeparameters at room temperature of a = 3.9298(3) Å and c = 7.7133(6) Å. The structure of UFe₅Si₃,which is new among intermetallic compounds, can be viewed as built up from an infinite three-dimensionalframework of Fe and Si atoms defining along the a direction, tunnels of hexagonal sections, where theU atoms lie. Alternating and direct current magnetic measurements reveal that UFe₅Si₃ behaves as ahard ferromagnet with a Curie temperature of about 310 K. Measurements on magnetically orientedpowder suggest that UFe₅Si₃ has a uniaxial anisotropy with c as the easy axis. The electrical resistivitydecreases monotonously with decreasing temperature suggesting no other magnetic transition below 300K. In line with this metallic behavior the thermal variation of the thermoelectric power remains of theorder of several V/K. A maximum around 60 K with a value of 12 V/K can be ascribed to Kondointeractions and/or crystalline electrical field effects.