Numéro
J. Phys. IV France
Volume 04, Numéro C4, Avril 1994
3rd International Conference Laser M2P
Page(s) C4-569 - C4-572
DOI http://dx.doi.org/10.1051/jp4:19944137
3rd International Conference Laser M2P

J. Phys. IV France 04 (1994) C4-569-C4-572

DOI: 10.1051/jp4:19944137

Optical spectroscopy of Eu3+ ion as a tool for the study of dehydration process in silica gels

A. PIAZZA1, A. BOUAJAJ1, 2, M. FERRARI1, M. MONTAGNA3, R. CAMPOSTRINI4 and G. CARTURAN4

1  CNR, Centro di Fisica degli Stati Aggregati ed Impianto Ionico, via Sommarive 14, 38050 Povo (TN), Italy
2  Physico-Chimie des Matériaux Luminescents, URA 172 du CNRS, Université Lyon I, 43 bd du 11 Novembre 1918, 69622 Villeurbanne, France
3  Dipartimento di Fisica, Università di Trento, via Sommarive 14, 38050 Povo (TN), Italy
4  Dipartimento di Ingegneria dei Materiali, Università di Trento, 38050 Mesiano (TN), Italy


Abstract
The structural modification induced by dehydration in optical silica gel has been studied using the spectroscopy of Eu3+ ion. The samples, doped with molar ratio Eu/Si = 0.01:1, were heated for 48 hours at different temperatures from 60 °C to 200 °C. Information on the dinamical properties of the local environment of the Eu3+ were obtained both by fluorescence and excitation measurements at T=11 K. The analysis of the 5D07F0 transition appears of particular relevance in this study, because the transition is between J=0 states and does not present internal structure. Its inhomogeneous linewidth gives a measure of the energy distribution of the different Eu3+ sites. Site selection spectroscopy was performed by exciting into the 5D1 state. Three different sets of sites were found. The phonon sidebands of the 5D0 ← F0 and 5D17F0 transitions were observed in the excitation spectra.



© EDP Sciences 1994