The indirect hyperfine interaction of a 29Si nearest neighbour to an oxygen defect in SiO2

A recent calculation determined the indirect aluminium hyperfine interactions for a number of oxygen-aluminium trapped-hole centres (Al3+-O-) in ionic crystals. One of these crystals was SiO2 where Al3+ is incorporated as an impurity. The theory showed that the dominant mechanism of the Al3+ transferred hyperfine interactions is exchanged polarisation. Since experimental data also exist for the Si4+ magnetic nuclei that are nearest neighbours to the Al3+-O- centre in SiO2, it is of interest to see if this same theory can account for the Si4+ transferred hyperfine interactions. This Letter reports on the results of calculating the Si4+ transferred hyperfine interactions for this system. The model has much the same level of success for the Si hyperfine interactions as for the Al.