New interpretation of the electronic structure of SiO2

The SiO₂ electronic density of states has been calculated within the Bethe lattice approximation using a simplified tight-binding hamiltonian. All of the experimentally found features, except a peak in the Si L_{2, 3} spectrum, are reproduced in our calculation when only unlike-atom bonds are present in the structure of the oxide. We have found that a possible origin of the peak in the Si L_{2, 3} spectrum is the presence of clusters of elemental Si in the oxide.