Magnetic Properties of Eu₃O₄

Abstract

A new Eu3O4 preparation method is described. Eu3O4 is produced by the solid state reaction between Eu and Eu2O3. Static magnetic susceptibility measurements were made by the Faraday method from 6 to 300°K. Eu3O4 was found to be ferrimagnetic with a Curie point of 77 °K.

The Binary Rare Earth Oxides

“…EuO has an unusual characteristic of being ferromagnetic, with a Curie temperature of 77 ( 1 K. 153 Europium in EuO holds a divalent state contrary to other rare earth monoxides. Eu 3 O 4 , prepared by the solid-state reaction between Eu and Eu 2 O 3 , is ferri-magnetic, with a Curie point of 77 K. 154 Each mole of Eu 3 O 4 possesses one Eu 2+ ion and two Eu 3+ ions. The praseodymium oxides with the compositions of PrO 1.50 , PrO 1.72 , PrO 1.83 , and PrO 2.00 155 have been reported to be paramagnetic at higher temperatures and obey the Curie-Weiss law.…”

“…Europium in EuO holds a divalent state contrary to other rare earth monoxides. Eu 3 O 4 , prepared by the solid-state reaction between Eu and Eu 2 O 3 , is ferrimagnetic, with a Curie point of 77 K . Each mole of Eu 3 O 4 possesses one Eu 2+ ion and two Eu 3+ ions.…”

Abrupt Europium Valence Change in Eu2Pt6Al15 around 45 K

“…However, the availability of a second oxidation state results in numerous interesting physical phenomena. Mixed valences can be found (Eu 3 O 4 , Sm 3 S 4 , Eu 3 S 4 , or EuPtP) as well as intermetallic valence fluctuation materials (e.g., CeAl 3 , Yb 4 Pt 9 Ga 24 , CeMo 2 Si 2 C, CeRu 1– x Ni x Al, Ce 2 Rh 3 Sn 5 , CeCu 2 Si 2 , EuCu 2 Si 2 , , YbCu 2 Si 2 ). A rather rare feature is a temperature or pressure dependent valence phase transition.…”

Synthesis, magnetic and NMR spectroscopic properties of the MAl5Pt3 series (M = Ca, Y, La–Nd, Sm–Er)

“…Cerium, europium and ytterbium intermetallics often exhibit interesting physical properties due to their two possible oxidation states. For cerium Ce 3+ ([Xe] 4f 1 ) and Ce 4+ ([Xe] 4f 0 ) are known while europium exhibits Eu 3+ ([Xe] 4f 6 ) and Eu 2+ ([Xe] 4f 7 ) and ytterbium Yb 3+ ([Xe] 4f 13 ) and Yb 2+ ([Xe] 4f 14 ). Of these, Ce 4+ and Yb 2+ are diamagnetic due to their empty and full 4f shell, respectively.…”

“…3 The availability of a second oxidation state, however, can result in numerous interesting physical phenomena. Static mixed valence states can be found (Eu 3 O 4 , 4–6 Eu 3 S 4 , 7 or EuPPt 8 ) as well as intermetallic valence fluctuation materials ( e.g. CeAl 3 , 9,10 Yb 4 Ga 24 Pt 9 , 11 CeMo 2 Si 2 C, 12 CeAlRu 1− x Ni x , 13 Ce 2 Sn 5 Rh 3 , 14 CeCu 2 Si 2 , 15 EuCu 2 Si 2 , 15,16 YbCu 2 Si 2 15 ).…”