Formally tetravalent cerium and thorium compounds: a configuration interaction study of cerocene Ce(C8H8)2 and thorocene Th(C8H8)2 using energy-adjusted quasirelativistic ab initio pseudopotentials

Dolg, Michael; Fulde, Peter; Stoll, Hermann; Preuß, H.; Chang, Agnes H. H.; Pitzer, Russell M.

doi:10.1016/0301-0104(94)00363-f

Cited by 131 publications

(195 citation statements)

References 40 publications

Supporting

Mentioning

175

Contrasting

Unclassified

Order By: Relevance

“…The relatively low percentages of 4f 1 character observed for these two compounds suggested that the LMCT configuration has a smaller contribution to the ground state than previously reported for (C8H8)2Ce, based on L3-edge XANES spectroscopy (89%) and multiconfiguration interaction calculations (80%). 96,164 To summarize, the experimental Ce L3-edge and M5,4-edge XANES measurements and CTM4XAS calculations all provide evidence for some mixing between the Ce 4f and ligand O 2p orbitals, as evidenced by L→Ce charge transfer contributions in the ground state. Within the bounds of an oxidation state formalism, CeLK4 is best regarded as tetravalent with a degree of covalency that is similar to compounds such as CeO2 and [Et4N]2[CeCl6], but less than that of (C8H8)2Ce.…”

Section: Resultsmentioning

confidence: 81%

A Macrocyclic Chelator That Selectively Binds Ln⁴⁺ over Ln³⁺ by a Factor of 10²⁹

et al. 2016

View full text Add to dashboard Cite

Abstract.A tetravalent cerium macrocyclic complex (CeLK4) was prepared with an octadentate terephthalamide ligand comprised of hard catecholate donors, and characterized in the solution state by spectrophotometric titrations and electrochemistry, and in the crystal by X-ray diffraction. The solution state studies showed that L exhibits a remarkably high affinity towards Ce 4+ , with log β110 = 61(2) and ΔG = -348 kJ/mol, compared with log β110 = 32.02(2) for the analogous Pr 3+ complex. In addition, L exhibits an unusual preference for forming CeL 4-relative to formation of the analogous actinide complex, ThL 4-, which has β110 = 53.7(5). The extreme stabilization of tetravalent cerium relative to its trivalent state is also evidenced by the shift of 1.91 V in redox potential of the Ce 3+ /Ce 4+ couple of the complex (measured at -0.454 V vs. SHE). The unprecedented behavior prompted an electronic structure analysis using L3 and M5,4-edge X-ray absorption near-edge structure (XANES) spectroscopies and configuration interaction calculations, which showed that 4f orbital bonding in CeLK4 has partial covalent character owing to ligand-to-metal charge transfer (LMCT) in the ground state. The experimental results are presented in the context of earlier measurements on tetravalent cerium compounds, indicating that the amount LMCT for CeLK4 is similar to that observed for [Et4N]2[CeCl6] and CeO2, and significantly less than that for the organometallic sandwich compound cerocene, (C8H8)2Ce. A simple model to rationalize changes in 4f orbitals for tri-and tetravalent lanthanide and actinide compounds is also provided.

show abstract

Section: Resultsmentioning

confidence: 81%

A Macrocyclic Chelator That Selectively Binds Ln⁴⁺ over Ln³⁺ by a Factor of 10²⁹

et al. 2016

View full text Add to dashboard Cite

show abstract

“…(3). Instead, a model where the first excited state is a triplet with Curie-Weiss paramagnetism can provide an excellent fit (available as Supporting Information).…”

Section: Discussionmentioning

confidence: 99%

“…Recent experimental and theoretical studies of certain Ce-and Yb-based organometallic complexes [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] have highlighted the importance of multiconfigurational interactions in understanding their electronic, structural, and magnetic properties. The canonical examples include Ce(cot) 2 , also known as "cerocene," where cot = cyclooctatetraene = C 8 H 8 , and Cp * 2 Yb(bipy), where Cp * = pentamethylcyclopentadienyl, and bipy = 2,2 ′ -bipyridine.…”

Section: Introductionmentioning

confidence: 99%

“…Interaction (CI) calculations [1][2][3][12][13][14][15] indicate that a singlet ground state develops that is lower in energy than that of the triplet state because it is a mixture of various open-and closed-shell singlet configurations. These singlet states are therefore multiconfigurational, that is, quantum mechanical admixtures of configurations with different f occupations, and are intermediate valent, abbreviated below as IV, in the sense that the effective valence for each Ce or Yb atom is non-integral.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Intermediate-Valence Tautomerism in Decamethylytterbocene Complexes of Methyl-Substituted Bipyridines

et al. 2010

View full text Add to dashboard Cite

“…Historically, the first theoretical work on U(COT) 2 including relativistic effects was done by Pyykkö and Lohr in 1981 [100] using relativistically parametrised extended Hückel calculations. Whereas a single-determinant wave function could describe the ground states of thorocene and uranocene [194,195], a multiconfigurational description of the wave function is needed for the later actinides [196,197]. For example, Kerridge and Kaltsoyannis [196] performed all-electron spin-orbit coupling complete active space self-consistent field calculations including dynamic correlation via second order perturbation theory (SOC-CASPT2) for the ground and low-lying excited states of M(COT) 2 (M=Th, U, Pu, Cm).…”

Section: Assessing Covalency In Nitrogen Ligand-actinide Complexesmentioning

confidence: 99%

Electronic structure theory to decipher the chemical bonding in actinide systems

Dognon

2017

Coordination Chemistry Reviews

View full text Add to dashboard Cite

International audienceThe chemical bonding in actinide compounds is usually analysed by inspecting the shape and the occupation of the orbitals or by calculating bond orders which are based on orbital overlap and occupation numbers. However, this may not give a definite answer because the choice of the partitioning method may strongly influence the result possibly leading to qualitatively different answers. In this review, we summarized the state-of-the-art of methods dedicated to the theoretical characterisation of bonding including charge, orbital, quantum chemical topology and energy decomposition analyses. This review is not exhaustive but aims to highlight some of the ways opened up by recent methodological developments. Various examples have been chosen to illustrate this progress

show abstract

Formally tetravalent cerium and thorium compounds: a configuration interaction study of cerocene Ce(C8H8)2 and thorocene Th(C8H8)2 using energy-adjusted quasirelativistic ab initio pseudopotentials

Cited by 131 publications

References 40 publications

A Macrocyclic Chelator That Selectively Binds Ln⁴⁺ over Ln³⁺ by a Factor of 10²⁹

A Macrocyclic Chelator That Selectively Binds Ln⁴⁺ over Ln³⁺ by a Factor of 10²⁹

Intermediate-Valence Tautomerism in Decamethylytterbocene Complexes of Methyl-Substituted Bipyridines

Electronic structure theory to decipher the chemical bonding in actinide systems

Contact Info

Product

Resources

About

Formally tetravalent cerium and thorium compounds: a configuration interaction study of cerocene Ce(C8H8)2 and thorocene Th(C8H8)2 using energy-adjusted quasirelativistic ab initio pseudopotentials

Cited by 131 publications

References 40 publications

A Macrocyclic Chelator That Selectively Binds Ln4+ over Ln3+ by a Factor of 1029

A Macrocyclic Chelator That Selectively Binds Ln4+ over Ln3+ by a Factor of 1029

Intermediate-Valence Tautomerism in Decamethylytterbocene Complexes of Methyl-Substituted Bipyridines

Electronic structure theory to decipher the chemical bonding in actinide systems

Contact Info

Product

Resources

About

A Macrocyclic Chelator That Selectively Binds Ln⁴⁺ over Ln³⁺ by a Factor of 10²⁹

A Macrocyclic Chelator That Selectively Binds Ln⁴⁺ over Ln³⁺ by a Factor of 10²⁹