biostudies-literatureLalli DMinistero dell???Istruzione, dell???Universit?? e della RicercaUniversit?? degli Studi del Piemonte OrientaleEuropean Cooperation in Science and Technology496-506https://www.ebi.ac.uk/biostudies/studies/S-EPMC8753608biostudies-literatureUnknown61(1)Typically, Ln(III) complexes are isostructural along the series, which enables studying one particular metal chelate to derive the structural features of the others. This is not the case for [Ln(AAZTA)(H₂O)<i>_x</i>]^- (<i>x</i> = 1, 2) systems, where structural variations along the series cause changes in the hydration number of the different metal complexes, and in particular the loss of one of the two metal-coordinated water molecules between Ho and Er. Herein, we present a ¹H field-cycling relaxometry and ¹⁷O NMR study that enables accessing the different exchange dynamics processes involving the two water molecules bound to the metal center in the [Gd(AAZTA)(H₂O)₂]^- complex. The resulting picture shoInorganic chemistrySurprising Complexity of the [Gd(AAZTA)(H₂O)₂]^- Chelate Revealed by NMR in the Frequency and Time Domains.PMC8753608FAR2019CA15209PRIN 2017A2KEPLPlatas-Iglesias CCarniato FTei LLalli DBotta MfalseSurprising Complexity of the [Gd(AAZTA)(H₂O)₂]^- Chelate Revealed by NMR in the Frequency and Time Domains.Typically, Ln(III) complexes are isostructural along the series, which enables studying one particular metal chelate to derive the structural features of the others. This is not the case for [Ln(AAZTA)(H₂O)<i>_x</i>]^- (<i>x</i> = 1, 2) systems, where structural variations along the series cause changes in the hydration number of the different metal complexes, and in particular the loss of one of the two metal-coordinated water molecules between Ho and Er. Herein, we present a ¹H field-cycling relaxometry and ¹⁷O NMR study that enables accessing the different exchange dynamics processes involving the two water molecules bound to the metal center in the [Gd(AAZTA)(H₂O)₂]^- complex. The resulting picture sho2022-01-01T00:00:00Z2022 Jan2026-05-08T16:37:21.05Z2026-04-08T00:08:55.741ZS-EPMC87536083489018210.1021/acs.inorgchem.1c03194