Lanthanide spectra energy differences

The most recent calculations, however, of the photoemission final state multiplet intensity for the 5 f initial state show also an intensity distribution different from the measured one. This may be partially corrected by accounting for the spectrometer transmission and the varying energy resolution of 0.12, 0.17, 0.17 and 1,3 eV for 21.2, 40.8, 48.4, and 1253.6 eV excitation. However, the UPS spectra are additionally distorted by a much stronger contribution of secondary electrons and the 5 f emission is superimposed upon the (6d7s) conduction electron density of states, background intensity of which was not considered in the calculated spectrum In the calculations, furthermore, in order to account for the excitation of electron-hole pairs, and in order to simulate instrumental resolution, the multiplet lines were broadened by a convolution with Doniach-Sunjic line shapes (for the first effect) and Gaussian profiles (for the second effect). The same parameters as in the case of the calculations for lanthanide metals were used for the asymmetry and the halfwidths ... 

Although no quantum confinement should occur in the electronic energy level structure of lanthanides in nanoparticles because of the localized 4f electronic states, the optical spectrum and luminescence dynamics of an impurity ion in dielectric nanoparticles can be significantly modified through electron-phonon interaction. Confinement effects on electron-phonon interaction are primarily due to the effect that the phonon density of states (PDOS) in a nanocrystal is discrete and therefore the low-energy acoustic phonon modes are cut off. As a consequence of the PDOS modification, luminescence dynamics of optical centers in nanoparticles, particularly, the nonradiative relaxation of ions from the electronically excited states, are expected to behave differently from that in bulk materials. 

Progress was made in the theoretical interpretation of the spectra of rare earth compounds and solutions in terms of energy level structure, in particular those of Pr3+ and Tm3+ with 4f2 and 4f12 configurations, respectively [123,124]. Differences in interpretation of the bands existed which were resolved in favour of f-f transitions [125]. Then the complex spectrum of Nd3+(4f3) was analyzed [126]. Jorgensen was one of the first to identify systematically the energy levels of lanthanide aquo ions [127]. 

Multilayer devices with lanthanide chelate complexes. In these complexes, efficient energy transfer from the singlet or triplet exciton on the ligand of the complex to the lanthanide atom at its center results in efficient, atomic-like line emission spectra from the latter. By adjusting the identity and concentration of the different lanthanide complex dopants, a line spectrum with white CIE coordinates was achieved.77... 

Comparison of K and L, absorption spectra (cf. fig. 6a), which both involve s-p transitions, demonstrates similar smooth variations of the absorption coefficient with energy. In the L, spectrum, however, fine structures can be resolved much more clearly than in the K spectrum F = 14 eV), due to the considerably smaller total width of the L, core hole (= 5eV). The spectral shape of the L, spectra in all lanthanide metals exhibits a stair-case-like rise of the absorption at threshold. A weak minimum is located at about 20 eV above the onset (figs. 6a). The fine structure of the L, spectra reflects sensitively local s- and p-type band states and their modifications through different types of chemical bonding or crystal symmetries (Lengeler and Zeller 1984). 

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