Zero-field J-spectroscopy of quadrupolar nuclei

Román Picazo-Frutos; Kirill F Sheberstov; John W Blanchard; Erik Van Dyke; Moritz Reh; Tobias Sjoelander; Alexander Pines; Dmitry Budker; Danila A Barskiy

doi:10.1038/s41467-024-48390-2

Zero-field J-spectroscopy of quadrupolar nuclei

Nat Commun. 2024 May 27;15(1):4487. doi: 10.1038/s41467-024-48390-2.

Authors

Román Picazo-Frutos^{1

2

3}, Kirill F Sheberstov^{1

2

3

4}, John W Blanchard^{1

2

3

5}, Erik Van Dyke^{1

2

3}, Moritz Reh^{6

7}, Tobias Sjoelander^{8

9

10}, Alexander Pines^{9

10}, Dmitry Budker^{1

2

3

6}, Danila A Barskiy^{11

12

13

14}

Affiliations

¹ Helmholtz-Institut Mainz, 55099, Mainz, Germany.
² Institute of Physics, Johannes Gutenberg-Universität Mainz, 55128, Mainz, Germany.
³ GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291, Darmstadt, Germany.
⁴ Department of Chemistry, École Normale Supérieure, PSL University, Paris, France.
⁵ Quantum Technology Center, University of Maryland, College Park, MD, USA.
⁶ Department of Physics, University of California-Berkeley, Berkeley, CA, 94720, USA.
⁷ Kirchhoff-Institut für Physik, Universität Heidelberg, Im Neuenheimer Feld 227, 69120, Heidelberg, Germany.
⁸ Department of Physics, University of Basel, Klingelbergstrasse 82, Basel, CH-4056, Switzerland.
⁹ Department of Chemistry, University of California, Berkeley, CA, 94720-3220, USA.
¹⁰ Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720-3220, USA.
¹¹ Helmholtz-Institut Mainz, 55099, Mainz, Germany. [email protected].
¹² Institute of Physics, Johannes Gutenberg-Universität Mainz, 55128, Mainz, Germany. [email protected].
¹³ GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291, Darmstadt, Germany. [email protected].
¹⁴ Department of Chemistry, University of California, Berkeley, CA, 94720-3220, USA. [email protected].

Abstract

Zero- to ultralow-field nuclear magnetic resonance (ZULF NMR) allows molecular structure elucidation via measurement of electron-mediated spin-spin J-couplings. This study examines zero-field J-spectra from molecules with quadrupolar nuclei, exemplified by solutions of various isotopologues of ammonium cations. The spectra reveal differences between various isotopologues upon extracting precise J-coupling values from pulse-acquire measurements. A primary isotope effect, $△ J = (γ_{^{14} N} / γ_{^{15} N}) J_{^{15} N H} - J_{^{14} N H} \approx - 58$ mHz, is deduced by analysis of the proton-nitrogen J-coupling ratios. This study points toward further experiments with symmetric cations containing quadrupolar nuclei, promising applications in biomedicine, energy storage, and benchmarking quantum chemistry calculations.