Atomic energy levels - the rare-earth elements :

Abstract

Only experimentally determined energy levels are included, the energies being restricted to excitations of outer-shell electrons and to inner-shell excitations up to the soft x-ray range. The levels were taken from analyses of the spectra of atomic gases wherever possible; however, the levels for several of the triply ionized rare earths are from analyses of the spectra of the ions in crystals or solutions. In addition to the level value (usually in units of cm 1 ) and the parity, the J value, configuration and term assignments, and the experimental g value are listed wherever available. Leading percentages from the calculated eigenvector are also tabulated for each level if available. The levels are grouped into spectroscopic terms of appropriate coupling schemes where such groups appear meaningful. Ionization potentials are tabulated for most of the spectra. Complete references for the tabulated data are given for each spectrum.

Ligand field density functional theory calculation of the 4f2 → 4f15d1 transitions in the quantum cutter Cs2KYF6:Pr3+

“…The energies corresponding to those spectroscopic terms are reported within the framework of the National Institute of Standards and Technologies (NIST) database. 52,53 The splitting of this excited electron configuration (4f 1 5d 1 ) due to the spin-spin and the spin-orbit couplings is determined to be about 18 000 cm À1 . 52,53 Using LFDFT, the energies of the 231 Slater determinants (91 for the 4f 2 and 140 for the 4f 1 5d 1 electron configurations) are calculated, which allows us to fit them to the H EE matrix elements and finally to extract 10 Slater-Condon parameters with a relatively small root mean square deviation.…”

“…52,53 The splitting of this excited electron configuration (4f 1 5d 1 ) due to the spin-spin and the spin-orbit couplings is determined to be about 18 000 cm À1 . 52,53 Using LFDFT, the energies of the 231 Slater determinants (91 for the 4f 2 and 140 for the 4f 1 5d 1 electron configurations) are calculated, which allows us to fit them to the H EE matrix elements and finally to extract 10 Slater-Condon parameters with a relatively small root mean square deviation. These parameters are presented in Table 1, together with the fitted parameters out of the multiplet splitting given in the NIST database.…”

“…To date, it has been reasonably measured to be about 48 000 cm À1 . 51 The excited electron configuration 4f 1 5d 1 has also been studied, 49,52 and in the emission spectroscopy, exactly 20 energy levels are observed. The energies corresponding to those spectroscopic terms are reported within the framework of the National Institute of Standards and Technologies (NIST) database.…”

Gas-Phase Reactions of Doubly Charged Lanthanide Cations with Alkanes and Alkenes. Trends in Metal(2+) Reactivity

“…As discussed below, Freiser and co-workers [8,11] proposed mechanisms in the case of La 2+ which explain the role of the d 1 configuration in hydrocarbon activation. There is a close correlation between the magnitudes of the promotion energies to the d 1 configuration of the Ln 2+ , and the promotion energies to the d 1 s 1 configuration of the corresponding Ln + [31]; this latter energy determines the efficiencies of these singly-charged ions toward hydrocarbon activation [29].…”

Gas-Phase Energetics of Actinide Oxides: An Assessment of Neutral and Cationic Monoxides and Dioxides from Thorium to Curium

“…This is rather clear in the case of the lanthanides and we suggest here that for the more "lanthanide-like" actinides the same relationship applies. The more common ground state configurations of the lanthanides are 4f n 6s 2 for the element, 4f n 6s 1 for the singly charged cation, and 4f n for the doubly charged [17]. Considering Am and also Bk, Cf, and Es, which all have ground sates similar to those of the more typical lanthanides, and also very reliable IE[An] [9] (see Table S4 Other data pertaining to the An metals that will be used in this assessment are the promotion energies from the ground levels of the An, An + , and An 2+ species to relevant, low-lying excited configurations; these data were retrieved from the standard sources [9,10a] (the values are collected in Tables S5, S6, and S7).…”