4f-4f intensities of the Tm3+ ions in fluoroindate glasses: the influence of third-order effects through odd intensity parameters

In this work an analysis of the phenomenological Omega(lambda) intensity parameters for the Tm3+ ion in fluoroindate glass is made using the standard Judd-Ofelt theory, and a modified oscillator strength taking into account odd-order contributions is utilized. Different sets of phenomenological intensity parameters Omega(lambda) (lambda=1,2,3,4,5,6) are discussed. The set of better quality is used to analyze the influence of third-order effects through odd intensity parameters in the new approximation. Fluoroindate glasses of compositions (40-x)InF3-20ZnF(2)-20SrF(2)-16BaF(2)-2GdF(3)-2NaF-xTmF(3) with x=1, 2 and 3 mol% were prepared, and the absorption spectra at room temperature in the spectral range from 300 to 2500 nm were obtained. The experimental oscillator strengths determined from the area under the absorption band are compared to the calculated ones. (C) 1998 Elsevier B.V. S.A.

Absorption and emission spectroscopic parameters of Nd3+ and Eu3+ ions in their hexamethylphosphoramide complexes

Syntheses of the following complexes are reported: LnX3·6L, LnX′3·4L, LnX″3·3L and Eu(NCS)3·3L, where Ln = Nd3+, Eu3+; L = hexamethylphosphoramide (hmpa); X = ClO4 -, PF6 -; X′ = NCS-, NO3 -, Br-, ClO4 -; X″=Cl-. Spectra of the complexes of Nd3+ (absorption) and Eu3+ (emission) in dichloromethane solutions were measured. The oscillator strengths of the Nd3+ f-f absorption bands within the 11 000-30 000 cm-1 region were determined and the τλ intensity parameters were obtained according to the Judd-Ofelt formalism. Covalency parameters were also determined for the Nd3+ complexes. The intensities relationship η21 of the 5D0→7F2 and 5D0→7F1 transitions of the Eu3+ was calculated. A good correlation between τ2 and the oscillator strength of the hypersensitive band of Nd3+ was found, as well as a correlation between τ2 and η21. There are only qualitative relations between τ2 and the covalency parameter. © 1991.

Judd-Ofelt analysis of Pr3+ ions in fluoroindate glasses: Influence of odd third order intensity parameters

In this work an analysis of the Judd-Ofelt phenomenological Ωλ intensity parameters for the Pr3+ ion in fluoroindate glass is made. Different Pr3+ concentrations, namely 1, 2, 3 and 4 mol% are used. The experimental oscillator strengths have been determined from the absorption spectra. A consistent set of parameters is obtained only with the inclusion of odd rank third order intensity parameters and if the band at 21 470 cm-1 is assigned to the 3H4 → 3P1 transition and the 1I6 component is incorporated in the 3H4 → 3P2 transition at 22 700 cm-1.