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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Ferromagnetism and structural transformations caused by Cr intercalation into TiTe(2)
N V Baranov1, V G Pleshchev, N V Selezneva
1Institute of Metal Physics, Russian Academy of Science, 620041 Ekaterinburg, Russia. Institute of Physics and Applied Mathematics, Ural State University, 620083 Ekaterinburg, Russia.
Abstract:
Crystal structure investigations, electrical resistivity, and magnetic measurements have been performed for polycrystalline samples of intercalated compounds Cr(x)TiTe(2) with a Cr concentration up to x = 0.65. According to the room-temperature x-ray diffraction study of Cr(x)TiTe(2), the initial hexagonal crystal structure transforms to a monoclinic one with increasing Cr content up to x≥0.5 due to the ordering of Cr ions. The intercalation results in the change of the resistivity behavior in Cr(x)TiTe(2) from metal-like at x = 0 to insulator-like above x = 0.33 and leads to ferromagnetic ordering of Cr magnetic moments at x≥0.5. For the compound Cr(0.25)TiTe(2), structural transformations and anomalous resistivity behavior are observed around 230 K, which cannot be explained only by the order-disorder transition within the subsystem of intercalated Cr ions. Structural changes within Te-Ti-Te sandwiches associated with charge density wave instability are suggested to be involved in this phase transition as well.
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