Ab initio calculations of the electronic structure of CeI3 monolayer

Objectives. In comparison with three-dimensional structures, two-dimensional (2D) magnetic materials are promising for use in spintronics and magnetic storage devices due to their exceptional characteristics and qualitatively different physical properties. Theoretical studies into 2D magnetic structures pave the way for the development of new compounds based on experimental data. In this work, we carry out a theoretical calculation of the electronic structure of a CeI₃ 2D-magnetic material, taking into account the Hubbard repulsion at the site, the partial density of electronic states (DOS), and the distribution of spin and charge densities.

Methods. Calculations of the electronic structure of the CeI₃ monolayer were performed using density functional theory (DFT) and the Hubbard Uscheme in the VASP software environment. The Dudarev method was used to account for the Hubbard correction.

Results. The calculated densities ofthe electronic states and the bandgap values for the ferro- and antiferromagnetic configurations of the material were found to be 1.98 and 2.08 eV, respectively. To assess the influence of correlation effects, the DOS was calculated both with and without the Hubbard correction. It was determined that the system in the ground magnetic state exhibits an antiferromagnetic ordering of the spin subsystem. The difference in the total energies of the antiferro- and ferromagnetic configurations was 2.8 meV per formula unit.

Conclusions. The calculations based on the Hubbard correction clearly demonstrated the presence of a bandgap, which is typical of semiconductor materials. The obtained bandgaps for the ferromagnetic and antiferromagnetic configurations of the system belong to the visible light range, which offers the opportunity of using 2D CeI₃ as a luminescent material in devices with a magnetically controlled emission. To assess the influence of correlation effects, the DOS was calculated both with and without the Hubbard correction. The obtained results agree with those obtained in experimental studies of cerium compounds. The consideration of correlation effects and spin polarization in the presented calculations forms the basis for further research into the magnetic properties of the CeI₃ monolayer for technological applications in the field of 2D magnetism.

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