Crystal-field analysis

The simple crystal field analysis of the effect of ligands on transition metal d-electron energies accords well with the deeper molecular orbital analysis (see e.g. [99]). In what way(s), however, is the crystal field method unrealistic ... 

Lochhead and Bray (1995) studied Eu3+ doped sodium disilicate glass with a high-pressure fluorescence line-narrowing technique. This technique was used to characterize the local structure of the Eu3+ ions up to a pressure of 21 GPa. For the crystal-field analysis they assumed a C2v site symmetry which allowed for a complete splitting of the crystal-field components. The crystal-field strength was determined according to eq. (11). The effect of pressure... 

Ideally, lanthanide ions occupy site with C3V symmetry when incorporated into the GaN lattice by substituting the Ga3+. However the actual site symmetry is often found lower than C3V due to strain and defects. So far no crystal field analysis has ever been reported for lanthanide-doped III-V QDs, due to the co-existence of multi-sites which complicates the energy level structure and makes crystal field analysis difficult. Site selective spectroscopy is a very useful tool thus proposed to investigate the different crystal field environments of lanthanide ions doped in III-V QDs. 

A first example is heptadentate 2,2,2"-tris(salicylideneimino)-triethylamine, H389 (fig. 76), which forms an isomorphous series of complexes [Ln(89)] (Bernhardt et al., 2000). A crystal field analysis based on polarized absorption and emission spectra of the trigonal... 

Crystal-Field Analysis of Ho3+-LaF3 and Er3+-LaF3 in C2V-Site Symmetry, W.T. Car-nail, G.L. Goodman, R.S. Rana, R Vandevelde, L. Fluyt, and C. Gorller-Walrand, J. Less-Common Met. 116, 17-29 (1986). 

Crystal-Field Analysis of Am3+ LaCl3/AmCl3 and Its Relationship to Spectra of Frozen Solutions of Am34 (aquo), W.T. Camall,./. Less-Common Met. 156, 221-235 (1989). 

Sun et al. (1985) found that replacement of Nd by Y, La or Ce does not have a pronounced effect on Tc. From an analysis of the anisotropy field JIA in the system (Nd1 xYx)2Fe14B, the same authors found evidence of the validity of the single-ion model for describing the magnetic anisotropy. The methodology of a multi-ion crystal-field analysis was discussed by Boltich (1988) and applied to the system ErxPr xFe14B. 

Trabelsi I, Maalej R, Dammak M, Lupei A, Kamoun M (2010) Crystal field analysis of Er in SC2O3 transparent ceramics. J Lumin 130 927-931... 

Site Symmetry Through Crystal-Field Analysis... 

Chang NC, Gruber JB, Leavitt RP, Morrison CA (1982) Optical spectra, eneigy levels, and crystal-field analysis of tripositive rare-earth ions in Y2O3. I. Kramtrs ions in C2 sites. J Chem Phys 76 3877... 

The molar absorptivity of the absorption spectra of in the presence of F was plotted as a function of wavenumber in Figure 6.4.1. When an absorption spectrum of 0.106M in the absence of F was measured, the molar absorptivities of each peak wavenumber at 14 903,16 501, and 22 123 cm agreed with the reported values [3]. The molar absorptivities at absorption peaks are shown in Table 6.4.1. By comparing these values with the crystal field analysis data of in CsCdBr3 [12] and LiYF4 [13], absorption bands... 

Karbowiak, M., Mech, A., and Drozdzynski, J. (2005) Absorption spectrum and crystal-field analysis of U4-t- ions in CsCdBrS single crystals. Chem. Phys, 308, 135. 

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