Bonding in tris(.eta.5-cyclopentadienyl) actinide complexes. 5. A comparison of the bonding in neptunium, plutonium, and transplutonium compounds with that in lanthanide compounds and a transition-metal analog

Crystal Field Strengths, Nephelauxetic Effects, and Experimentally Based Molecular Orbital Schemes (in the f Range) of Selected Cyclopentadienyl Complexes of Samarium(III)

“…[66] In Figure 5, the experimentally based non-relativistic MO schemes (in the f range) of complex 1 and [Pr(η 5 -C 5 H 4 SiMe 3 ) 3 ] [52] are compared with the non-relativistic MO scheme of fictive ψ trigonal planar [Sm(η 5 -Cp) 3 ] calculated in the framework of the SW-Xα approximation. [33] Obviously, the calculated splitting of f orbitals is considerably greater than the experimentally based ones. Moreover, the experimentally based sequences of f orbitals are roughly comparable for 1 and [Pr( .…”

“…The electronic structure of fictive ψ trigonal planar [Pr(Cp) 3 ] was calculated by means of the SW-Xα [33] as well as the INDO/1 [35] approximation. The SW-Xα calculation yielded a comparable MO scheme (in the f range) as for [Sm(Cp) 3 ] [33] and the more basic INDO/1 calculation led, astonishingly, to the same energetic sequence [35] as we had concluded for [Pr(η 5 -C 5 H 4 SiMe 3 ) 3 ] ( Figure 5).…”

Electronic Structure of Organometallic Complexes of f Elements. Are Molecular Orbital Calculations a Useful Tool for Spectroscopists?

“…In Fig. 1 this experiment based CF splitting pattern is compared with the results of calculations for fictive trigonal planar Cp 3 Ρr [25]. Obviously, the calculated total splitting of f orbitals is a factor of 2 greater than the experimental one.…”

Group 3 metal stilbene complexes: synthesis, reactivity, and electronic structure studies

“…For example, rare-earths show similar chemical reactivity within the series despite a different number of f electrons, because these electrons are shielded. 1,2 On the other hand, actinides, of which uranium and thorium are studied the most, show involvement of f electrons in bonding, [3][4][5][6] and uranium has several oxidation states accessible. 7 The differences between lanthanides and early actinides are most striking in their organometallic chemistry.…”

“…7 The differences between lanthanides and early actinides are most striking in their organometallic chemistry. 4,5 Group 3 metals (scandium, yttrium, lanthanum, and lutetium) usually show chemistry representative of all rare earths and their compounds are easier to characterize because of their diamagnetic nature. 8,9 Their classification with lanthanides rather than with transition metals is supported by the fact that, with few exceptions, 9 their complexes contain the metal in the +3 oxidation state, while transition metals display multiple oxidation states.…”