Crystal structure of UT2Zn20 (T=Fe, Co, Ru, Rh, and Ir) phases

“…Fig.1a depicts the essential features associated with the CeCr 2 Al 20 type structure. The detailed discussion about the structure can be found elsewhere in literature [10,11]. Here we emphasize that all the compounds crystallize in cubic structure with space group F d3m (Refer Fig.2).…”

Section: Physical Propertiesmentioning

confidence: 98%

“…[7,8,9]. Frank-Kasper cage compounds are an interesting class of materials which are investigated extensively in literature [10,11,12] owing to their strong correlation behaviour, unusual thermoelectric properties [13], rattling phenomena of guest ions [14] superconductivity and multipolar ordering [15]. These compounds crystallize in the CeCr 2 Al 20 type cubic structure with space group F d3m.…”

Section: Introductionmentioning

confidence: 99%

Magnetic, specific heat and electrical transport properties of Frank–Kasper cage compounds RTM₂Al₂₀[R = Eu, Gd and La; TM = V, Ti]

Kumar

Nair

Reinke

et al. 2016

J. Phys.: Condens. Matter

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Abstract. Single crystals of Frank-Kasper compounds RTM 2 Al 20 (R = Eu, Gd and La; TM = V and Ti) were grown by self-flux method and their physical properties were investigated through magnetization (M ), magnetic susceptibility (χ), specific heat (C P ) and electrical resistivity (ρ) measurements. Powder x-ray diffraction studies and structural analysis showed that these compounds crystallize in the cubic crystal structure with the space group F d3m. The magnetic susceptibility for the compounds EuTi 2 Al 20 and GdTi 2 Al 20 showed a sudden jump below the Néel temperature T N indicative of plausible double magnetic transition. Specific heat (C P ) and electrical resistivity (ρ) measurements also confirm the first-order magnetic transition (FOMT) and possible double magnetic transitions. Temperature variation of heat capacity showed a sharp phase transition and huge C P value for the (Eu/Gd)Ti 2 Al 20 compounds Full width at half-maximum (FWHM) < 0.2 K) which is reminiscent of a first-order phase transition and a unique attribute among RTM 2 Al 20 compounds. In contrast, linear variation of C P is observed in the ordered state for (Eu/Gd)V 2 Al 20 compounds suggesting a λ-type transition. We observed clear anomaly between heating and cooling cycle in temperature-time relaxation curve for the compounds GdTi 2 Al 20 (2.38 K) and EuTi 2 Al 20 (3.2 K) which is indicating a thermal arrest due to the latent heat. The temperature variation of S mag for GdTi 2 Al 20 saturates to a value 0.95R ln 8 while the other magnetic systems exhibited still lower entropy saturation values in the high temperature limit. (C P − γT )/T 3 vs T plot showed a maximum near 27 K for all the compounds indicating the presence of low frequency Einstein modes of vibrations. Resistivity measurements showed that all the samples behave as normal Fermi liquid type compounds and ρ(T ) due to electron-phonon scattering follows Bloch-Grüneisen-Mott relation in the paramagnetic region.

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“…For a comprehensive discussion of the crystal structures of the RX 2 M 20 compounds the interested reader is referred to Refs. [4,24].…”

Section: Crystal Structurementioning

confidence: 99%