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  • Spectroscopic and electrochemical characterization of a Pr 4+ imidophosphorane complex and the redox chemistry of Nd 3+ and Dy 3+ complexes
Title: Spectroscopic and electrochemical characterization of a Pr 4+ imidophosphorane complex and the redox chemistry of Nd 3+ and Dy 3+ complexes
The molecular tetravalent oxidation state for praseodymium is observed in solution via oxidation of the anionic trivalent precursor [K][Pr 3+ (NP(1,2-bis- t Bu-diamidoethane)(NEt 2 )) 4 ] (1-Pr(NP*)) with AgI at −35 °C. The Pr 4+ complex is characterized in solution via cyclic voltammetry, UV-vis-NIR electronic absorption spectroscopy, and EPR spectroscopy. Electrochemical analyses of [K][Ln 3+ (NP(1,2-bis- t Bu-diamidoethane)(NEt 2 )) 4 ] (Ln = Nd and Dy) by cyclic voltammetry are reported and, in conjunction with theoretical modeling of electronic structure and oxidation potential, are indicative of principal ligand oxidations in contrast to the metal-centered oxidation observed for 1-Pr(NP*). The identification of a tetravalent praseodymium complex in in situ UV-vis and EPR experiments is further validated by theoretical modeling of the redox chemistry and the UV-vis spectrum. The latter study was performed by extended multistate pair-density functional theory (XMS-PDFT) and implicates a multiconfigurational ground state for the tetravalent praseodymium complex.  more » « less
Award ID(s):
1943452
NSF-PAR ID:
10341736
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Dalton Transactions
Volume:
51
Issue:
17
ISSN:
1477-9226
Page Range / eLocation ID:
6696 to 6706
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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