The vibronic spectroscopy and luminescence concentration quenching of the Pr 3+ ion in La 2O 3, LaOF and LiYF 4

• Published in: The Journal of physics and chemistry of solids Vol. 56; no. 2; pp. 267 - 276
• Main Authors: De Mello Donegá, C., Dirksen, G.J., Folkerts, H.F., Meijerink, A., Blasse, G.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 1995
• Subjects: A. inorganic compounds; A. optical materials; D. luminescence; D. phonons; D. phonons; D. luminescence; A. optical materials; A. inorganic compounds
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/0022-3697(94)00175-8

The luminescence spectra of the Pr 3+ ion in (La 1− x Pr x) 2O 3 ( x ⩽ 0.2), La 1− x Pr xOF and LiY 1− x Pr xF 4 ( x ⩽ 0.1) powder samples and in LiY 1− x Pr xF 4 ( x ⩽ 0.02) single crystals have been investigated. The concentration quenching of the Pr 3+ emission is observed to be stronger in (La 1− x Pr x) 2O 3. This is ascribed to a more efficient cross-relaxation via superexchange interaction between Pr 3+ ions. This interaction is shown to be effective over longer distances in La 2O 3:Pr than in LiYF 4:Pr (viz. 10 and 5 Å, respectively). The shift of the 4f5d configuration to lower energies with increasing Pr 3+ concentration, which is only observed for (La 1− x Pr x) 2O 3, gives support for this conclusion. Moreover, the vibronic spectra and the vibronic transition probabilities of Pr 3+ in LaOF and La 2O 3 are reported and compared.