Structural and optical studies of Eu3+/nanocrystallites doped titania-zirconia hybrids

Titania-zirconia matrices co-doped with europium ions and CdS/CdSe nanocrystallites were prepared through the sol-gel route. The phonon sideband (PSB) analysis of the excitation spectrum provides information about the coupling between vibrational modes and electronic transitions. The vibrational state energy and the local site symmetry in the titania-zirconia matrix around Eu3+ ions were investigated in detail. The emission spectrum intensities of electric dipole transitions, with respect to magnetic dipole transition, gives a measure of the distortion from the inversion symmetry around the Eu3+ site. The vibrational state bands along with Raman measurements give information on the structural units in the vicinity of the dopant ion. A correlation between the Raman spectral data and phonon sideband analysis yields an average structure of the bulk glass and a near estimate of the maximum vibrational state energy.