X-Band Parallel-Mode and Multifrequency Electron Paramagnetic Resonance Spectroscopy of = 1/2 Bismuth Centers

Overview

Journal Inorg Chem

Specialty Chemistry

Date 2022 Jul 14

PMID 35834368

Authors

Julia Haak

Julia Kruger

Nikolay V Abrosimov

Christoph Helling

Stephan Schulz

George E Cutsail Iii

Affiliations

Soon will be listed here.

Abstract

The recent successes in the isolation and characterization of several bismuth radicals inspire the development of new spectroscopic approaches for the in-depth analysis of their electronic structure. Electron paramagnetic resonance (EPR) spectroscopy is a powerful tool for the characterization of main group radicals. However, the large electron-nuclear hyperfine interactions of Bi (Bi, = 9/2) have presented difficult challenges to fully interpret the spectral properties for some of these radicals. Parallel-mode EPR (∥) is almost exclusively employed for the study of > 1/2 systems but becomes feasible for = 1/2 systems with large hyperfine couplings, offering a distinct EPR spectroscopic approach. Herein, we demonstrate the application of conventional X-band parallel-mode EPR for = 1/2, = 9/2 spin systems: Bi-doped crystalline silicon (Si:Bi) and the molecular Bi radicals [L(X)Ga]Bi (X = Cl or I) and [L(Cl)GaBi(cAAC)] (L = HC[MeCN(2,6-PrCH)]). In combination with multifrequency perpendicular-mode EPR (X-, Q-, and W-band frequencies), we were able to fully refine both the anisotropic - and -tensors of these molecular radicals. The parallel-mode EPR experiments demonstrated and discussed here have the potential to enable the characterization of other = 1/2 systems with large hyperfine couplings, which is often challenging by conventional perpendicular-mode EPR techniques. Considerations pertaining to the choice of microwave frequency are discussed for relevant spin-systems.

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References

Pierce B, Elgren T, Hendrich M . Mechanistic implications for the formation of the diiron cluster in ribonucleotide reductase provided by quantitative EPR spectroscopy. J Am Chem Soc. 2003; 125(29):8748-59. DOI: 10.1021/ja021290h. View

Helling C, Cutsail 3rd G, Weinert H, Wolper C, Schulz S . Ligand Effects on the Electronic Structure of Heteroleptic Antimony-Centered Radicals. Angew Chem Int Ed Engl. 2020; 59(19):7561-7568. PMC: 7216903. DOI: 10.1002/anie.202000586. View

Weinert H, Wolper C, Haak J, Cutsail 3rd G, Schulz S . Synthesis, structure and bonding nature of heavy dipnictene radical anions. Chem Sci. 2021; 12(42):14024-14032. PMC: 8565390. DOI: 10.1039/d1sc04230k. View

Oberdorf K, Hanft A, Ramler J, Krummenacher I, Bickelhaupt F, Poater J . Bismuth Amides Mediate Facile and Highly Selective Pn-Pn Radical-Coupling Reactions (Pn=N, P, As). Angew Chem Int Ed Engl. 2020; 60(12):6441-6445. PMC: 7986226. DOI: 10.1002/anie.202015514. View

Petasis D, Hendrich M . A new Q-band EPR probe for quantitative studies of even electron metalloproteins. J Magn Reson. 1999; 136(2):200-6. DOI: 10.1006/jmre.1998.1657. View

Ganesamoorthy C, Helling C, Wolper C, Frank W, Bill E, Cutsail 3rd G . From stable Sb- and Bi-centered radicals to a compound with a Ga=Sb double bond. Nat Commun. 2018; 9(1):87. PMC: 5758792. DOI: 10.1038/s41467-017-02581-2. View

Lichtenberg C . Well-Defined, Mononuclear Bi(I) and Bi(II) Compounds: Towards Transition-Metal-Like Behavior. Angew Chem Int Ed Engl. 2015; 55(2):484-6. DOI: 10.1002/anie.201509234. View

Hagen W, Albracht S . Analysis of strain-induced EPR-line shapes and anisotropic spin-lattice relaxation in a [2Fe-2S] ferredoxin. Biochim Biophys Acta. 1982; 702(1):61-71. DOI: 10.1016/0167-4838(82)90027-9. View

Hendrich M, Debrunner P . Integer-spin electron paramagnetic resonance of iron proteins. Biophys J. 1989; 56(3):489-506. PMC: 1280502. DOI: 10.1016/S0006-3495(89)82696-7. View

10.

Reijerse E, Lendzian F, Isaacson R, Lubitz W . A tunable general purpose Q-band resonator for CW and pulse EPR/ENDOR experiments with large sample access and optical excitation. J Magn Reson. 2011; 214(1):237-43. DOI: 10.1016/j.jmr.2011.11.011. View

11.

Helling C, Wolper C, Cutsail 3rd G, Haberhauer G, Schulz S . A Mechanistic Study on Reactions of Group 13 Diyls LM with Cp*SbX : From Stibanyl Radicals to Antimony Hydrides. Chemistry. 2020; 26(59):13390-13399. PMC: 7693246. DOI: 10.1002/chem.202001739. View

12.

Wolfowicz G, Urdampilleta M, Thewalt M, Riemann H, Abrosimov N, Becker P . Conditional control of donor nuclear spins in silicon using stark shifts. Phys Rev Lett. 2014; 113(15):157601. DOI: 10.1103/PhysRevLett.113.157601. View

13.

Mohammady M, Morley G, Monteiro T . Bismuth qubits in silicon: the role of EPR cancellation resonances. Phys Rev Lett. 2010; 105(6):067602. DOI: 10.1103/PhysRevLett.105.067602. View

14.

Morley G, Warner M, Stoneham A, Greenland P, van Tol J, Kay C . The initialization and manipulation of quantum information stored in silicon by bismuth dopants. Nat Mater. 2010; 9(9):725-9. DOI: 10.1038/nmat2828. View

15.

Hagen W . Very Low-Frequency Broadband Electron Paramagnetic Resonance Spectroscopy of Metalloproteins. J Phys Chem A. 2021; 125(15):3208-3218. PMC: 8154605. DOI: 10.1021/acs.jpca.1c01217. View

16.

Schwamm R, Lein M, Coles M, Fitchett C . Catalytic oxidative coupling promoted by bismuth TEMPOxide complexes. Chem Commun (Camb). 2018; 54(8):916-919. DOI: 10.1039/c7cc08402a. View

17.

Kruger J, Wolper C, Schulz S . Stepwise Bi-Bi Bond Formation: From a Bi-centered Radical to Bi Butterfly and Bi Cuneane-Type Clusters. Inorg Chem. 2020; 59(15):11142-11151. DOI: 10.1021/acs.inorgchem.0c01657. View

18.

Kruger J, Haak J, Wolper C, Cutsail 3rd G, Haberhauer G, Schulz S . Single-Electron Oxidation of Carbene-Coordinated Pnictinidenes-Entry into Heteroleptic Radical Cations and Metalloid Clusters. Inorg Chem. 2022; 61(15):5878-5884. DOI: 10.1021/acs.inorgchem.2c00249. View

19.

Lichtenberg C . Molecular bismuth(III) monocations: structure, bonding, reactivity, and catalysis. Chem Commun (Camb). 2021; 57(37):4483-4495. DOI: 10.1039/d1cc01284c. View

20.

Ishida S, Hirakawa F, Furukawa K, Yoza K, Iwamoto T . Persistent antimony- and bismuth-centered radicals in solution. Angew Chem Int Ed Engl. 2014; 53(42):11172-6. DOI: 10.1002/anie.201405509. View