Judd-Ofelt intensity parameters

EXAMPLE 6.6 The Judd-Ofelt intensity parameters experimentally obtained... 

Selected Judd-Ofelt intensity parameters for Ln111 ions in units of 10-20 cm2... 

The eight-coordinate tetrakis(diethyldithiocarbamate) lanthanide complexes are isomor-phous and the lanthanum complex has a quasi-tetrahedral configuration of the four CS2 chelate groups. The transition frequencies and dipole strengths of these complexes available over the accessible f-f manifold allowed the extraction of the Judd-Ofelt intensity parameters Qx for k = 2, 4, 6 by standard least squares methods [112,113]. The values of observed Qx and calculated Q, values are given in Table 8.10. The three components of f2() are... 

Here 2 are the Judd-Ofelt intensity parameters which can be found in reference 1 ... 

Krupke (63) calculated fluorescence intensities and the radiative lifetime of 5f- for Pm YAG using Judd-Ofelt intensity parameters extrapolated from Nd3+. The Fq-9- 15 transition at 0.92 ym had an oscillator strength within 70% of the value for the F3/2" In/2 transition of Nd YAG. The SF-j jg 0f the transition and transitions from the thermally populated 2 state are also intense and laser candidates. 

Oscillator strengths and Judd-Ofelt intensity parameters of LnX3... 

The energy level scheme of Pm is very similar to that of Nd and hence is attractive for laser action. There are numerous absorption bands for optical pumping and fluorescence from the Fi state to levels of to % occurs at wavelengths ranging from =0.81 to 1.72 m. Krupke (1972), using Judd-Ofelt intensity parameters extrapolated from Nd ", calculated fluorescence intensities and the F, lifetime for Pm YAG. The most promising transitions for lasing are Fi L at 0.92/ m and at 1.09 m, both of which have predicted... 

FT-IR Fourier transform infrared Tx Judd-Ofelt intensity parameter... 

Here O, are the Judd-Ofelt intensity parameters, (/l t/ / ) is the matrix element of the transition between the ground and excited state of the sensitizer and activator, respectively. [The calculation of these matrix elements in the intermediate-coupling scheme is now a well-known procedure and may be found in Reisfeld (1976a) and Riseberg and Weber (1976)]. S is the overlap integral and R is the interionic distance. 

Despite the presence of organic counterparts and therefore higher phonon energies, Er emission may be observed in OIH as well. As an example, Er -doped diureasils were obtained from different carboxylic acid solvolysis routes [44]. Characterization techniques included X-ray absorption (EXAFS) at the Er Lm-edge, FTIR, and photoluminescence. Judd-Ofelt intensity parameters (Q ) were evaluated from absorption measurements together with the Er Iis/2 radiative lifetime (trad) and the peak emission cross section (cem)- Values so... 

Values of the Judd-Ofelt intensity parameters, /2a, for the lanthanides in dilute acid solution". 

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