Electron spin resonance parameters of cation vacancies in tin dioxide doped with fluorine and hydrogen

The spin Hamiltonian parameters of intrinsic defects in tin dioxide (SnO2) doped with fluorine or hydrogen are examined through the first-principles electronic structure calculations based on density functional theory (DFT). The electron paramagnetic resonance signals with g-tensor value in the range of 1.89-1.94 were found for tin vacancy (V-Sn) and its complex with oxygen vacancy (V-Sn-V-O) associated with a donor like interstitial hydrogen or fluorine, substituting oxygen. The calculated parameters are consistent with experimental observations, which indicate that Sn vacancies may be present in SnO2 at essentially higher concentration than it is predicted by DFT based on the formation energies calculations. Within the second coordination shell of the tin vacancy, the V-O may stabilize in the singly ionized charge state, which is otherwise considered to be unstable for isolated oxygen vacancy in the bulk of SnO2. (C) 2013 AIP Publishing LLC.