2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/151728We point out that contrary to a recent suggestion by Boero et al. (PRL 78, 887 (1997)) the +1 charge state of the oxygen vacancy in alpha-quartz cannot be invoked as a candidate E' center in alpha-quartz and silica.submitted to PRL as a CommentMaterials Sciencetext