Flux Growth and Magnetoresistance Behavior of Rare Earth Zintl Phase EuMgSn

Abstract

Reactions of europium and tin in 1:1 Mg/Al mixed flux produce large crystals of EuMgSn. This phase crystallizes with the TiNiSi structure type in orthorhombic space group Pnma (a = 8.0849(7) Å, b = 4.8517(4) Å, c = 8.7504(8) Å, Z = 4, R1 = 0.0137). The crystal structure features europium cations positioned between puckered hexagonal layers comprised of magnesium and tin atoms. Magnetic susceptibility measurements indicate the europium in this phase is divalent, which suggests that the compound is possibly valence-balanced as Eu(2+)Mg(2+)Sn(4-). However, EuMgSn is a metal as indicated by density of states calculations and electrical resistivity behavior. This phase exhibits antiferromagnetic ordering at T(N) = 10.9 K at low field (100 G) and the ordering temperature decreases when a higher magnetic field is applied. ac magnetization and field dependence of resistivity at 4.2 K reveal that there is a spin reorientation at 2 T, in agreement with the metamagnetic transition shown in the dc magnetization versus field data. Temperature dependence of resistivity at 2.5 T indicates that EuMgSn has a large magnetoresistance up to -30% near its magnetic ordering temperature.

Complex physical properties of EuMgSi – a complementary study by neutron powder diffraction and151Eu Mössbauer spectroscopy

“…Furthermore, two distinct anomalies are also reported for the isotypic compounds EuMgGe 25 and EuMgSn54 . In contrast to Ma et al we do not believe that the ordering temperature depends significantly on the orientation of the crystals and causes the observed two anomalies.…”

“…This might be intrinsic or due to a minor impurity phase, but it is certainly not compatible with a simple antiferromagnetic ordering. A second, more 54 If this would be the case, only one broad singularity would be visible in the temperature dependence of the specific heat in the absence of an external magnetic field for a powdered sample.…”

RFe2Mg Al8− (R=La–Nd and Sm; x≈0.8): Flux synthesis, structure, magnetic and electrical properties

“…All of these units share trigonal faces, forming chains running along the c-direction. All the FeAl 6 clusters are also connected in the ab-plane in two different ways: half of them are monocapped by bridging Al sites, similar to the chains of FeAl 6 clusters seen in R 5 (Mg/Al) 5 Fe 4 (Al/Si) 18 (R=Gd, Dy and Y) and R 3 Fe(Mg/Al) 4 Si 2[15,16]. The other half are bicapped by two aluminum atoms on both sides.…”

“…Instead, hybridization between Ce 4f electrons and the conduction electrons leads to a metallic Fermi-liquid ground state, as characterized by the electrical resistivity, thermoelectric power and heat capacity [11][12][13]. 18 (R=Gd, Dy and Y) and EuMgSn [15,16]. The large single crystals produced in this flux allowed for the study of interesting antiferromagnetic behavior in these compounds.…”

Metal flux synthesis and atom probe tomography analyses of different intermetallic al–mg phases

“…A large variety of intermetallic aluminides have been prepared from liquid Al, and many of them feature fascinating new structures. Many of these intermetallic aluminides are also key components in advanced Al alloys [5][6][7]. In particular, the use of an Al/Mg mixture is of practical interest [7].…”