Shift reagent

{
  "id": "MLC-T-CHM-010822",
  "term": "Shift reagent",
  "field": "Chemistry",
  "definition": "A paramagnetic substance, usually a lanthanide complex such as Eu(fod)3 or Eu(dpm)3, that binds to polar functional groups and shifts the NMR resonances of nearby nuclei by an amount that depends on distance and geometry. The shift is mainly pseudocontact in origin and falls off roughly as the inverse cube of the distance from the metal, with an angular factor. Chiral lanthanide reagents such as Eu(hfc)3 split the signals of enantiomers.",
  "subject": "Organic and Biomolecular Chemistry",
  "references": [
    "PAC, 2022, 94, 353. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 2021)' on page 502 (https://doi.org/10.1515/pac-2018-1010)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/shift-reagent/"
}