Cr-Doped TiSe₂ – A Layered Dichalcogenide Spin Glass

We report the magnetic characterization of the Cr-doped layered dichalcogenide TiSe 2 . The temperature dependent magnetic susceptibilities are typical of those seen in geometrically frustrated insulating antiferromagnets. The Cr moment is close to the spin-only value, and the Curie–Weiss temperatures (θ cw ) are between −90 and −230 K. Freezing of the spin system, which is glassy, characterized by peaks in the ac and dc susceptibility and specific heat, does not occur until below T /θ cw = 0.05. The CDW transition seen in the resistivity for pure TiSe 2 is still present for 3% Cr substitution but is absent by 10% substitution, above which the materials are metallic and p -type. Structural refinements, magnetic characterization, and chemical considerations indicate that the materials are of the type Ti 1– x Cr x Se 2- x /2 for 0 ≤ x ≤ 0.6.