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Title: Evaluating electrochemical accessibility of 4f n 5d 1 and 4f n+1 Ln( ii ) ions in (C 5 H 4 SiMe 3 ) 3 Ln and (C 5 Me 4 H) 3 Ln complexes
The reduction potentials (reported vs. Fc + /Fc) for a series of Cp′ 3 Ln complexes (Cp′ = C 5 H 4 SiMe 3 , Ln = lanthanide) were determined via electrochemistry in THF with [ n Bu 4 N][BPh 4 ] as the supporting electrolyte. The Ln( iii )/Ln( ii ) reduction potentials for Ln = Eu, Yb, Sm, and Tm (−1.07 to −2.83 V) follow the expected trend for stability of 4f 7 , 4f 14 , 4f 6 , and 4f 13 Ln( ii ) ions, respectively. The reduction potentials for Ln = Pr, Nd, Gd, Tb, Dy, Ho, Er, and Lu, that form 4f n 5d 1 Ln( ii ) ions ( n = 2–14), fall in a narrow range of −2.95 V to −3.14 V. Only cathodic events were observed for La and Ce at −3.36 V and −3.43 V, respectively. The reduction potentials of the Ln( ii ) compounds [K(2.2.2-cryptand)][Cp′ 3 Ln] (Ln = Pr, Sm, Eu) match those of the Cp′ 3 Ln complexes. The reduction potentials of nine (C 5 Me 4 H) 3 Ln complexes were also studied and found to be 0.05–0.24 V more negative than those of the Cp′ 3 Ln compounds.  more » « less
Award ID(s):
1855328
NSF-PAR ID:
10349291
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Dalton Transactions
Volume:
50
Issue:
40
ISSN:
1477-9226
Page Range / eLocation ID:
14384 to 14389
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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