Structures and Magnetic Properties of Ternary Lithium Oxides Li<i>R</i>O₂ (<i>R</i> = Rare Earths)

Abstract

Crystal structures and magnetic properties of ternary lithium oxides LiRO2 (R = rare earths) are investigated. Their crystal structures are grouped into four type structures (α, β, γ, δ-types). From their low-temperature X-ray diffraction and differential thermal analysis measurements, the LiRO2 compounds with R = Dy, Ho, Y, and Er transform from the monoclinic β-type (low-temperature phase) to the tetragonal α-type structures (high-temperature phase) at 475, 360, 325, and 200 K, respectively. Through their magnetic susceptibility and specific heat measurements, the Sm, Gd, Dy, and Er compounds show antiferromagnetic transitions at 1.9, 2.5, 3.0, and 4.2 K, respectively. Both LiNdO2 and LiYbO2 show magnetic anomaly below 1.8 K.