The Pb center at the (111) Si/SiO2 interface in porous material was investigated by means of electron-nuclear double resonance techniques. A new spectrum was observed which was attributed to superhyperfine interaction of the Pb center with the nuclei of H atoms which passivated the dangling bonds of 3 next-nearest neighbor shells at the interfacial plane. Isotropic and anisotropic superhyperfine constants were evaluated for these shells.

V.J.Bratus, S.S.Ishchenko, S.M.Okulov, I.P.Vorona, H.J.Von Bardeleben: Materials Science Forum, 1995, 196-201, 529-34