More Like this

1. Multisite Ligand Noninnocence of (Cp ^N3 )Fe(CO) ₃ ⁺ with Exogenous Hydride Donors: Kinetics and Mechanism

   https://doi.org/10.1021/acs.organomet.4c00137  

   VanderWeide, Andrew I; Neugebauer, Hagen; Goel, Bhumika; Tresp, David S; Pena, Deuris; Grimme, Stefan; Hansen, Andreas; Prokopchuk, Demyan E (August 2024, Organometallics)
2. “Catch and release” of the Cp ^N3 ligand using cobalt: dissociation, protonation, and C–H bond thermochemistry

   https://doi.org/10.1039/D4DT01560F  

   Luhach, Sanju; Lalancette, Roger A; Prokopchuk, Demyan E (January 2024, Dalton Transactions)

   Coordination of the amine-rich Cp^N3ligand to cobalt is reported. Ligand displacement leads to ligand protonation and evaluation of the metal-free C–H bond thermochemistry, revealing a weak homolytic C–H bond dissociation free energy (52 kcal mol⁻¹). 

   more » « less
3. Crystal structure of the [(THF)Cs(μ-η ⁵ :η ⁵ -Cp′) ₃ Yb] _n oligomer

   https://doi.org/10.1107/S2056989020008051  

   Huh, Daniel N.; Ziller, Joseph W.; Evans, William J. (July 2020, Acta Crystallographica Section E Crystallographic Communications)

   null (Ed.)

   The green compound poly[(tetrahydrofuran)tris[μ-η 5 :η 5 -1-(trimethylsilyl)cyclopentadienyl]caesium(I)ytterbium(II)], [CsYb(C 8 H 13 Si) 3 (C 4 H 8 O)] n or [(THF)Cs(μ-η 5 :η 5 -Cp′) 3 Yb II ] n was synthesized by reduction of a red THF solution of (C 5 H 4 SiMe 3 ) 3 Yb III with excess Cs metal and identified by X-ray diffraction. The compound crystallizes as a two-dimensional array of hexagons with alternating Cs I and Yb II ions at the vertices and cyclopentadienyl groups bridging each edge. This, based off the six-electron cyclopentadienyl rings occupying three coordination positions, gives a formally nine-coordinate tris(cyclopentadienyl) coordination environment to Yb and the Cs is ten-coordinate due to the three cyclopentadienyl rings and a coordinated molecule of THF. The complex comprises layers of Cs 3 Yb 3 hexagons with THF ligands and Me 3 Si groups in between the layers. The Yb—C metrical parameters are consistent with a 4 f 14 Yb II electron configuration. 

   more » « less
4. Identification of an X-Band Clock Transition in Cp′ ₃ Pr ^– Enabled by a 4f ² 5d ¹ Configuration

   https://doi.org/10.1021/jacs.3c12725  

   Smith, Patrick W.; Hrubý, Jakub; Evans, William J.; Hill, Stephen; Minasian, Stefan G. (March 2024, Journal of the American Chemical Society)

   Molecular qubits offer an attractive basis for quantum information processing, but challenges remain with regard to sustained coherence. Qubits based on clock transitions offer a method to improve the coherence times. We propose a general strategy for identifying molecules with high-frequency clock transitions in systems where a d electron is coupled to a crystal-field singlet state of an f configuration, resulting in an MJ = ±1/2 ground state with strong hyperfine coupling. Using this approach, a 9.834 GHz clock transition was identified in a molecular Pr complex, [K(crypt)][Cp′3PrII], leading to 3-fold enhancements in T2 relative to other transitions in the spectrum. This result indicates the promise of the design principles outlined here for the further development of f-element systems for quantum information applications. 

   more » « less
5. Synthesis and Crystallographic Characterization of a Reduced Bimetallic Yttrium ansa -Metallocene Hydride Complex, [K(crypt)][(μ-Cp ^An )Y(μ-H)] ₂ (Cp ^An = Me ₂ Si[C ₅ H ₃ (SiMe ₃ )-3] ₂ ), with a 3.4 Å Yttrium–Yttrium Distance

   https://doi.org/10.1021/jacs.3c01405  

   Wedal, Justin C.; Anderson-Sanchez, Lauren M.; Dumas, Megan T.; Gould, Colin A.; Beltrán-Leiva, María J.; Celis-Barros, Cristian; Páez-Hernández, Dayán; Ziller, Joseph W.; Long, Jeffrey R.; Evans, William J. (May 2023, Journal of the American Chemical Society)