We study the magnetic and electronic properties of defects in ${\text{SnO}}_2$ using pseudopotential and all electron methods. Our calculations show that bulk ${\text{SnO}}_2$ is nonmagnetic, but it shows magnetism with a magnetic moment around $4.00{\mu }_B$ due to Sn vacancy $\left(V_{\text{Sn}}\right)$. The magnetic moment comes mainly from O atoms surrounding $V_{\text{Sn}}$ and Sn atoms, which couple antiferromagnetically with the O atoms in the presence of $V_{\text{Sn}}$. The coupling between different Sn vacancies is also studied and we found that these defects not only couple ferromagnetically but also antiferromagnetically and ferrimagnetically. Our calculations demonstrate that the experimentally observed giant magnetic moment of transition–metal-doped ${\text{SnO}}_2$ can be attributed to $V_{\text{Sn}}$.

• Received 12 September 2008

DOI:https://doi.org/10.1103/PhysRevB.78.184404