INELASTIC NEUTRON SCATTERING STUDY OF DISPERSE SILICAS SURFACE ZONE VIBRATIONS

E. Sheka1, V. Khavryutchenko2, I. Natkaniec3, I. Markichev1, V. Ogenko2

1 Russian Peoples' Friendship University, Moscow, Russia,
2 Institute of Surface Chemistry, Ukrainian Academy of Sciences, Kiev, Ukraine,
3 Joint Institute for Nuclear Research, Dubna, Russia

A detailed analysis of doubly-weighted density of vibrational states (AWDS) spectra obtained for a set of disperse silica species by inelastic neutron scattering at 10 K is presented. Every disperse silica is considered consisting of a silica core and of a surface zone of a complicate structure.The experimental AWDS spectra are decomposed into the above constituents basic spectra. A comparative study of the basic spectra of four species families: aerosil, two silica gels and aerogel, has exhibited that the studied species belong to different structural classes of amorphous silica.