Magnetic order in Pu₂M₃Si₅ (M = Co, Ni)

E D Bauer; P H Tobash; J N Mitchell; J A Kennison; F Ronning; B L Scott; J D Thompson

doi:10.1088/0953-8984/23/9/094223

Magnetic order in Pu₂M₃Si₅ (M = Co, Ni)

J Phys Condens Matter. 2011 Mar 9;23(9):094223. doi: 10.1088/0953-8984/23/9/094223.

Authors

E D Bauer¹, P H Tobash, J N Mitchell, J A Kennison, F Ronning, B L Scott, J D Thompson

Affiliation

¹ Los Alamos National Laboratory, Los Alamos, NM 87545, USA.

PMID: 21339576
DOI: 10.1088/0953-8984/23/9/094223

Abstract

The physical properties including magnetic susceptibility, specific heat, and electrical resistivity of two new plutonium compounds Pu2M3Si5 (M = Co, Ni) are reported. Pu2Ni3Si5 crystallizes in the orthorhombic U2Co3Si5 structure type, which can be considered a variant of the BaAl4 tetragonal structure, while Pu2Co3Si5 adopts the closely related monoclinic Lu2Co3Si5 type. Magnetic order is observed in both compounds, with Pu2Ni3Si5 ordering ferromagnetically at T(C) = 65 K then undergoing a transition into an antiferromagnetic state below T(N) = 35 K. Two successive magnetic transitions are also observed at T(mag1) = 38 K and T(mag2) = 5 K in Pu2Co3Si5. Specific heat measurements reveal that these two materials have a moderately enhanced Sommerfeld coefficient γ ∼ 100 mJ/mol Pu K(2) in the magnetic state with comparable RKKY and Kondo energy scales.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.