Structural Properties and Magnetic Phase Transition of Self-Intercalated CrTeX Compound*

Magnetic transition-metal dichalcogenides (TMDs) have been of particular interest due to their unique magnetic properties and layered structure that can be useful in the field of spintronics. Self-intercalation of transition metals in the van der Waals (vdW) gaps of the TMDs can alter the structural and magnetic properties of the material to create new, interesting compounds. We report a self-intercalated compound CrTe_1.64 that forms a three-dimensional (2x2x2) superstructure with inequivalent occupation of the Cr atoms intercalated in the vdW gaps. This structure is confirmed using X-ray diffraction (XRD) and Transmission Electron Microscope (TEM) measurements. In addition to this, magnetic measurements show an out-of-plane easy-axis with Curie temperature (T_c) of approximately 195 K and an emergent antiferromagnetic ordering just above the T_c. This research shows that self-intercalation of magnetic TMDs can provide a method of tuning magnetic and structural properties of the material.