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Updated: May 2, 2026
Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
Charge and magnetic states of rutile TiO2 doped with Cr ions
Rokyeon Kim1, Suyeon Cho, Won-Goo Park
1CSCMR, Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Korea.
Abstract:
We observe that the electronic and magnetic properties of Cr-doped rutile TiO2 single crystals are highly dependent on growth conditions. The ferromagnetic component of magnetic susceptibility is observed to be enhanced for samples grown under oxygen-rich conditions. To understand the charge state of Cr dopants and their role in response to an external magnetic field, we carry out density functional theory calculations for Cr-doped rutile TiO2. Using the results of formation energy calculations in the presence of oxygen vacancies and Cr atom substitution at the Ti sites, we demonstrate that the Cr3+ state is a source of Curie-Weiss-type magnetic response, whereas the Cr4+ defect states contribute to the ferromagnetic component. We also provide the electronic structures of various defect configurations and attempt to explain the optical and electronic properties of the Cr-doped system.
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