Magnetic behavior in LiNbO3 nanocrystallites caused by oxygen vacancies

• Oxygen vacancies were formed at the surface of LiNiO3 nanocrystals by a temperature programmed reduction process.
• The observed ferromagnetism in LiNbO3 nanocrystals after a treatment in a reducing atmosphere shows no temperature dependence in the range of 4–300 K.
• Magnetization based on density functional theory calculations was compared with the experimental data.

Ferromagnetism is observed in LiNiO3 nanocrystals exposed to a reducing atmosphere intended to create oxygen vacancies. The existence of vacancies is confirmed by measuring the oxygen depletion across the selected nanoparticles by TEM. The magnetism shows no temperature dependence in the range of 4–300 K. The density functional theory was used to perform spin polarized electronic structure calculations for LiNiO3 with and without oxygen vacancies. The calculated magnetic data qualitatively support the observed magnetic behavior.