Mössbauer and magnetic susceptibility investigations of strontium, lanthanum and europium transition metal phosphides with ThCr2Si2 type structure

doi:10.1016/0022-3697(88)90030-3

Journal of Physics and Chemistry of Solids

Volume 49, Issue 7, 1988, Pages 785-795

https://doi.org/10.1016/0022-3697(88)90030-3 Get rights and content

Abstract

The magnetic properties of the compounds AT₂P₂ (A = Sr, La, Eu; T = Fe, Co) and EuNi₂P₂ were studied by ⁵⁷Fe and ¹⁵¹Eu Mössbauer spectroscopy, and magnetic susceptibility measurements. SrFe₂P₂ and LaFe₂P₂ are Pauli paramagnets, while SrCo₂P₂ is weakly magnetic with a broad maximum in the susceptibility curve at 115K, which is rationalized by a weak interaction between the itinerant electrons. LaCo₂P₂ and EuFe₂P₂ are ferromagnets with a Curie temperature of T_c = 125 ± 3K and T_c = 27.5 ± 0.5 K. EuCo₂P₂ orders antiferromagnetically at the Néel temperature T_N = 66.5 ± 0.5 K. The intermediate valence compound EuNi₂P₂ shows no magnetic order down to 4.2 K. The interaction between the localized europium moments of EuFe₂P₂ and EuCo₂P₂ is rationalized by the RKKY theory. In these compounds the temperature dependences of the europium sublattice magnetizations do not exactly follow the Brillouin curve for $J= 72$ , indicating the influence of the conduction bands. The results demonstrate that the iron and cobalt sublattices do not participate in the magnetic ordering of the europium containing compounds.

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Mössbauer and magnetic susceptibility investigations of strontium, lanthanum and europium transition metal phosphides with ThCr2Si2 type structure

Abstract

J. Phys. Chem. Solids

J. Solid St. Chem.

J. Solid St. Chem.

Phys. Lett.

Phys. Lett.

J. Magn. Magn. Mater.

J. Magn. Magn. Mater.

J. Magn. Magn. Mater.

J. Magn. Magn. Mater.

Solid St. Commun.

J. Phys. Chem. Solids

J. Magn. Magn. Mater.

J. Phys. Chem. Solids

J. Magn. Magn. Mater.

J. Phys. Chem. Solids

J. Solid St. Chem.

Z. Naturf.

Z. anorg. allg. Chem.

Mössbauer and magnetic susceptibility investigations of strontium, lanthanum and europium transition metal phosphides with ThCr₂Si₂ type structure