Effects of oxygen vacancy on the magnetic properties of Cr-doped SnO2: Density functional investigation

Magnetic properties of Cr-doped SnO2 and the effects of oxygen vacancy (VO) on the magnetic properties are examined to understand the origin of ferromagnetism in Cr-doped SnO2 and explain the observed discrepant phenomena. Cr-doped SnO2 shows a p–d hopping ferromagnetic interaction that decreases gradually with the increase in Cr–Cr distance. In Cr-doped SnO2 with VO, ferromagnetic interaction is obviously weakened. Exchange constants indicate that the ferromagnetic exchange interaction in Cr-doped SnO2 is similar to that in Co-doped SnO2, while it is similar to that in Fe-doped SnO2 and/or undoped SnO2 with tin vacancy (VSn) in the presence of VO.