Magnetic properties of Cr-intercalated TiSe 2

Abstract

Using the measurements of the susceptibility and magnetization in steady and pulsed magnetic fields and under applied hydrostatic pressure we have investigated the magnetic properties of Cr-intercalated Cr x TiSe 2 compounds having a hexagonal crystal structure of a quasi-two-dimensional type. It has been found that the effective magnetic moment μ eff of Cr changes nonmonotonously with Cr-content. The μ eff( x) dependence correlates with the change in the interlayer distance at the intercalation which is attributed to the change of the localization degree of the chromium 3d-electrons. The intercalation leads to changes of the magnetic state of Cr x TiSe 2 from the Pauli paramagnetism at x=0 to the claster-glass behavior at 0.25≤ x≤0.33 and then to the antiferromagnetic order in Cr 0.5TiSe 2. The last compound exhibits a field-induced spin-flip transition below the Néel temperature T N=38 K due to the very low ratio between the interlayer and intralayer exchange interaction ( w 2/ w 1≈5.4×10 −3). The applied hydrostatic pressure decreases the Néel temperature with a rate d T N/d p=−0.19 K/kbar. The interlayer exchange interaction was found to be more sensitive to the Cr–Cr distance than the intralayer one.