Absorption Spectra of Octahedral Lanthanide Hexahalides

Ryan, J.L.; Jørgensen, Chr. Klixbüll

doi:10.1021/j100881a021

Cited by 308 publications

(144 citation statements)

References 5 publications

Supporting

Mentioning

119

Contrasting

Order By: Relevance

“…spectra of transition metal ions, c.t. transitions have also been reported for the trivalent lanthanides Eu 3+, Sm 3÷, Tm 3+ and Yb 3+ in complexes with halogen ligands [5] and in oxides [6], in which the first band in the absorption spectra is ascribed to such a transition, in contrast with Ce 3+, Pr 3+ and Tb 3+ where the first band is assigned to a 4[--, 5d transition, a markedly different feature being the bandwidth, which is almost twice as large for a c.t. band compared with an f--, d band [7].…”

mentioning

confidence: 72%

“…mainly localized on the metal ion. In Ce 3+ the 4f ~ 5d transitions occur at about 30 kK [5,12] and in Pr 3+ and Tb 3+ at even higher wavenumbers, so that for the tetravalent ions these transitions are expected at much higher energies. This leaves only the latter assignment, i.e.…”

Section: Discussionmentioning

confidence: 99%

“…bands for complexes of the tetravalent lanthanide (Ln) ions Ce 4+, Pr 4+ and Tb 4+ in an easily accessible region of the spectrum. In fact some years ago Ryan and Je~rgensen [5] have reported the absorption spectra of CeCI6 z--and CeBr6'-and Je~rgensen and Rittershaus [8] described the diffuse reflection spectra of Pr '+ and Tb '+ in TbO2 and Y:O3 in which the broad bands in the visible region of the spectrum were ascribed to c.t. transitions.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Charge-transfer spectra of tetravalent lanthanide ions in oxides

Hoefdraad

1975

Journal of Inorganic and Nuclear Chemistry

116

View full text Add to dashboard Cite

Abstract--The charge-transfer spectra of Ce 4~, Pr "+ and Yb "+ in a number of oxides are reported. It is noted that the position of the first charge-transfer band is fixed for the metal ion in an oxygen coordination of V1, but varies in VIII coordination as a function of the host lattice. It is argued that this variation is inherent to the VIII coordination itself.INTRODUCTION IN THE past decade quite some work has been done on charge transfer (c.t.) transitions in molecular or ionic groups in which an electron is excited from a delocalized ligand molecular orbital (m.o.) to an empty or incompletely filled orbital mainly localized on the central ion of the chromophore. The position of the first c.t. band of a complex is determined by the oxidizing character of the central ion and by the properties of the set of ligands. Thus not only the reducing character of a particular ligand is of importance, but also effects due to ligand-ligand repulsion and to destabilization of the metal ion orbitals due to interaction with ligand m.o. 's[l--4].Although most data refer to c.t. spectra of transition metal ions, c.t. transitions have also been reported for the trivalent lanthanides Eu 3+, Sm 3÷, Tm 3+ and Yb 3+ in complexes with halogen ligands [5] and in oxides [6], in which the first band in the absorption spectra is ascribed to such a transition, in contrast with Ce 3+, Pr 3+ and Tb 3+ where the first band is assigned to a 4[--, 5d transition, a markedly different feature being the bandwidth, which is almost twice as large for a c.t. band compared with an f--, d band [7].Since for a given element the c.t. bands shift to lower energies with increasing oxidation state, and transitions between different cationic subshells (Rydberg transitions) to higher energies, one might expect to find the c.t. bands for complexes of the tetravalent lanthanide (Ln) ions Ce 4+, Pr 4+ and Tb 4+ in an easily accessible region of the spectrum. In fact some years ago Ryan and Je~rgensen [5] have reported the absorption spectra of CeCI6 z--and CeBr6'-and Je~rgensen and Rittershaus[8] described the diffuse reflection spectra of Pr '+ and Tb '+ in TbO2 and Y:O3 in which the broad bands in the visible region of the spectrum were ascribed to c.t. transitions. Recently the spectra of these ions in monoclinic ZrO2 have been reported [9]. It was noted that in ZrO2 and Y203 the bands of Pr 4+ and Tb 4+ are situated at markedly higher energies than in ThO2, a fact which cannot readily be understood.Most complexes have been studied in solution, but in this case, since it is not possible to obtain Pr '+ and Tb 4~ complexes in solution, it was necessary to work in solid samples. Solutions have the advantage that absorption spectra can be obtained, whereas solid samples can only be studied by reflection spectroscopy, because it is usually difficult to obtain single crystals. On the other hand solid samples enable a systematic study of c.t. bands in several crystal lattices, with the central metal ion in a wide

show abstract

mentioning

confidence: 72%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Charge-transfer spectra of tetravalent lanthanide ions in oxides

Hoefdraad

1975

Journal of Inorganic and Nuclear Chemistry

116

View full text Add to dashboard Cite

show abstract

“…They are particularly striking in octahedral LnCl6-3 and LnBr6-3 [26] and LnI6-3 [27] studied in acetonitrile solution, and later in cubic elpasolites Cs2 NaLnΧ6 . Electron transfer bands can also be observed [28] in the ultraviolet in europium(III) acquoions, sulfate complexes etc., and in crystalline ternary oxides [29] containing europium(III), the relatively most oxidizing Ln(ΙII).…”

Section: Introductionmentioning

confidence: 93%

“…The (unusual) octahedral coordination [26] in CeCl6-3 corresponds to a strong, not exceedingly broad, absorption band at 30300 cm-1 and of CeBr6-3 at 29150 cm-1 . The most unexpected result is that the subshell energy difference Δ is at least 15000 cm -1 , more than half the observed value [1,3] in pronounced covalent IrCl fi 3 and IrBr6-3 .…”

Section: Introductionmentioning

confidence: 98%

Rationalization of Spectra of Rare Earths in Condensed Matter

Reisfeld

Jørgensen

1993

Acta Phys. Pol. A

View full text Add to dashboard Cite

The parametrized models are compared with counter-intuitive consequences of the non-relativistic Schrödinger treatment. For both 4 f q, 5f q and d9 systems in condensed matter, the energy levels must be strongly influenced by correlation effects. The parametrization of intensities is conceptually very different for f' and d9 compounds. The bandwidths of absorption and luminescence are discussed and related to the Born-Oppenheimer factorization.

show abstract