Molecular dynamics simulation has been used to study the e!ect of hydrostatic pressure on the structural and spectroscopic properties of Eu>-doped Na O) 2SiO glass. The short-and medium-range order has been investigated. The evolution of angular and radial distribution has shown the dependence of the structure with pressure. It was found that pressure induces an increase of the coordination number of the Eu> ion and a shortening in the Eu}O bond distance. The pressure e!ects on the crystal-"eld parameters and on the luminescent spectra are computed and discussed in comparison with experimental data. 2000 Elsevier Science B.V. All rights reserved.