Field-dependent paramagnetic relaxation enhancement in solutions of Ni(II): What happens above the NMR proton frequency of 1 GHz?

Jozef Kowalewski; Pascal H Fries; Danuta Kruk; Michael Odelius; Andrei V Egorov; Steffen Krämer; Holger Stork; Mladen Horvatić; Claude Berthier; (deceased)

doi:10.1016/j.jmr.2020.106737

Field-dependent paramagnetic relaxation enhancement in solutions of Ni(II): What happens above the NMR proton frequency of 1 GHz?

J Magn Reson. 2020 May:314:106737. doi: 10.1016/j.jmr.2020.106737. Epub 2020 Apr 24.

Authors

Jozef Kowalewski¹, Pascal H Fries², Danuta Kruk³, Michael Odelius⁴, Andrei V Egorov⁵, Steffen Krämer⁶, Holger Stork⁶, Mladen Horvatić⁶, Claude Berthier⁶; (deceased)

Affiliations

¹ Department of Materials and Environmental Chemistry, Stockholm University, SE-116 91 Stockholm, Sweden. Electronic address: jozef.kowalewski@mmk.su.se.
² Univ. Grenoble Alpes, CEA, IRIG-MEM, 38000 Grenoble, France.
³ University of Warmia and Mazury in Olsztyn, Faculty of Mathematics and Computer Science, Sloneczna 54, PL-10710 Olsztyn, Poland.
⁴ Department of Physics, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm, Sweden.
⁵ St.Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg 199034, Russia.
⁶ Laboratoire National des Champs Magnétiques Intenses, LNCMI-CNRS (UPR3228), EMFL, Univ. Grenoble Alpes, INSA Toulouse, Univ. Toulouse Paul Sabatier, B.P. 166, 38042 Grenoble Cedex 09, France.

PMID: 32380383
DOI: 10.1016/j.jmr.2020.106737

Abstract

An extended set of paramagnetic relaxation enhancement (PRE) data, up to the field of 32.9 Tesla, is reported for protons in an acidified aqueous solution of a Ni(II) salt in the presence and in the absence of added glycerol. For the 55% w/w glycerol sample, a distinct maximum in the PRE vs magnetic field curve is observed for the first time. The data are analysed using the Swedish slow-motion theory, including both the intramolecular (inner-sphere) and intermolecular (outer-sphere) contributions. The results indicate that estimating the outer-sphere part in the presence of the more efficient inner-sphere term is a difficult task.

Keywords: Molecular dynamics; NMR; Paramagnetic relaxation enhancement.

Publication types

Research Support, Non-U.S. Gov't