Magnetic Properties of the Ordered Double Perovskite Sr₂MnTeO₆

Abstract

The ordered double perovskite Sr 2 MnTeO 6 was prepared by the freeze-drying method. The nuclear and magnetic structures were determined by both X-ray and neutron (D2B and D1B) powder diffraction. A distorted, double perovskite structure type described by the monoclinic P12 1 /n1 space group is observed at room temperature and down to 4 K. The room temperature EPR spectrum shows an isotropic signal centered at a g value of 1.998 indicating that manganese ions are in the +2 oxidation state. At low temperature the EPR signal broadens as the exchange and dipolar interactions between Mn 2+ cations increase. Below 25 K no signal is observed, indicating that the sample is magnetically ordered. The dc magnetic susceptibility shows the existence of antiferromagnetic interactions with an ordering temperature

Microstructural Origin of Magnetic and Giant Dielectric Behavior of Sr2MnTiO6−δ Perovskite Nanocrystals

“…It is also worth noting that the Weiss constant values are all high and negative, θ=−336 and −417 K, in both ranges of temperature, which can be related to AFM interactions. Such a response appears to be expected in a perovskite only containing Mn 4+ as paramagnetic cations, as has been observed in similar systems 30,32 . However, other authors have reported 24 previously that FM interactions are operative in SMTO.…”

“…This is not surprising considering the oxidation states and sizes of cations located at the B-sublattice (almost only Mn 41 and Ti 41 ), in contrast to the case of wellknown double perovskites. [28][29][30] Another interesting result obtained by this technique is the stabilization of surprisingly small crystals (considering the thermal treatment used), clearly below 50 nm in all cases, as shown in Fig. 5 as an example.…”

“…Such a response appears to be expected in a perovskite only containing Mn 41 as paramagnetic cations, as has been observed in similar systems. 30,32 However, other authors have reported 24 previously that FM interactions are operative in SMTO. This apparent contradiction could be explained if we take into account that the results obtained by these authors corresponded to a sample that was synthesized by the ceramic method.…”

Synthesis and structural and magnetic characterization of the frustrated magnetic system La2Ni4/3−Co Sb2/3O6

“…Under these conditions only nnn and tnn interactions are possible and for this kind of materials antiferromagnetic transitions are observed below 30 K: Sr 2 MnTeO 6 [37], LaSrMnNbO 6 [38], La 2 CoTiO 6 and La 2 NiTiO 6 [39], LaBaTaNiO 6 and LaBaTaCoO 6 [40], LaPbM SbO 6 where M¼Mn, Co and Ni [41], among others.…”

Effect of Si(iv) substitution on electrochemical, magnetic and spectroscopic performance of nanosized LiMn2−xSixO4

“…As a result, as the Mn(III)/Mn(IV) ratio becomes larger, the peak to peak linewidth ΔH pp value also increases. 21 . Figure 7 shows the thermal evolution of χ m T of all the samples.…”