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29Si Hyperfine Structure of the E'_αCenter in Amorphous Silicon Dioxide

G. Buscarino·S. Agnello·F. M. Gelardi
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Abstract

We report a study by electron paramagnetic resonance (EPR) on the E'_αpoint defect in amorphous silicon dioxide (a-SiO2). Our experiments were performed on gamma-ray irradiated oxygen-deficient materials and pointed out that the 29Si hyperfine structure of the E'_alpha consists in a pair of lines split by 49 mT. On the basis of the experimental results a microscopic model is proposed for the E'_alpha center, consisting in a hole trapped in an oxygen vacancy with the unpaired electron sp3 orbital pointing away from the vacancy in a back-projected configuration and interacting with an extra oxygen atom of the a-SiO2 matrix.

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G. Buscarino, S. Agnello, F. M. Gelardi. 2006-09-25. 29Si Hyperfine Structure of the E'_αCenter in Amorphous Silicon Dioxide. https://doi.org/10.1103/physrevlett.97.135502

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