Challenges in intermetallics: synthesis, structural characterization, and transitions

Abstract

Intermetallics that contain rare-earth elements are particularly interesting because of their temperature- and pressure-dependent structural and physical transitions that make them potential candidates for magnetic applications. This article highlights synthetic routes and structural characterization advancements used to investigate intermetallic materials. Experimental and theoretical examples of three intermetallic structure types--ThCr(2)Si(2), Heusler and Laves--are discussed to present a historical review and to illustrate the grand challenges in unravelling structure-property relationships of intermetallic compounds.

Complex magnetic phase diagram with multistep spin-flop transitions in La0.25Pr0.75CoTan1, Garlea2, Kovnir3 et al. 2017Phys. Rev. B12130View full textAdd to dashboardCite

“…Measurements were performed on a sample of ~8 g held in a cylindrical vanadium container placed in a top-loading closed cycle refrigerator, covering a temperature range of 4-300 K. Measurements under applied magnetic field from 0 to 7 T were performed on pelletized samples, to avoid reorientation of the crystallites. The data were collected by scanning the detector array consisting of 44 3 He tubes in two segments, to cover the total 2θ range of 7°-133° in steps of 0.05°. Rietveld refinement of the collected data was carried out using FULLPROF software [20].…”

“…Electrical transport measurements were conducted on an oriented single crystal in an Oxford 3 He system with the Van der Pauw configuration. The AC current was applied in the ab plane and the obtained voltage was measured by lock-in detection.…”

“…AT 2 X 2 compounds with layered ThCr 2 Si 2 -type structure, where A is a rare earth, alkaline earth, or alkali metal, T is a transition metal, and X is a metalloid element, represent a large class of materials with long-standing interest in their structural, transport, and magnetic properties [1][2][3][4][5]. This interest was reinvigorated by the discovery of iron-based high-temperature superconductors in 2008 [6].…”

Microwave synthesis and magnetic properties of Laves‐type Ti2M3Si (M = Mn, Fe, Co, Ni)

“…In order to study their functionality and properties high-quality samples in bulk amounts need to be prepared. The synthesis of intermetallics in general holds some challenges as a few issues need be considered [2]. For example, melting points of metals often easily exceed 1000 8C, but can be significantly lower for a combination of elements.…”

“…Thirdly, most metals easily form oxides when reacted in air, thus special care needs to be taken to work under inert conditions, for example using quartz ampoules. For the preparation of polycrystalline intermetallics, arc melting has been proven to be a useful technique [2]. However, very high reaction temperatures may induce structural defects as a result of vaporization of certain elements in the precursor mixture.…”