title: Magnetic structure of the antiferromagnetic Kondo lattice compounds CeRhAl₄Si₂ and CeIrAl₄Si₂.
abstract: We have investigated the magnetic ground state of the antiferromagnetic Kondo-lattice compounds CeMAl4Si2(M = Rh, Ir) using neutron powder diffraction. Although both of these compounds show two magnetic transitions T(N1) and T(N2) in the bulk properties measurements, evidence for magnetic long-range order was only found below the lower transition T(N2). Analysis of the diffraction profiles reveals a commensurate antiferromagnetic structure with a propagation vector k = (0, 0, 1/2). The magnetic moment in the ordered state of CeRhAl4Si2 and CeIrAl4Si2 were determined to be 1.14(2) and 1.41(3) μ(B) Ce(-1), respectively, and are parallel to the crystallographic c-axis in agreement with magnetic susceptibility measurements.
authors.affiliation: Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors.forename: N J
authors.initials: NJ
authors.lastname: Ghimire
authors.forename: S
authors.initials: S
authors.lastname: Calder
authors.forename: M
authors.initials: M
authors.lastname: Janoschek
authors.forename: E D
authors.initials: ED
authors.lastname: Bauer