Term: correlation spectroscopy
https://doi.org/10.1351/goldbook.08323

Definition:
Homonuclear two-dimensional nuclear magnetic resonance spectroscopy correlation experiment showing cross peaks representing spin-spin coupling between pairs of nuclei.

Notes:
1) COSY is the simplest and original 2D experiment, but still one of the most common along with its many variations including those with multiple quantum filters, solvent suppression and optimization for long range couplings.
2) COSY is often used to show the spin-spin coupling between hydrogen nuclei 2 or 3 bonds apart (\(\ce{H,H}\mbox{-}\rm{COSY}\)).

Related Term: two-dimensional nuclear magnetic resonance spectroscopy (http://doi.org/10.1351/goldbook.08439).

Source: PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 684 (https://doi.org/10.1515/pac-2019-0203)

Citation: 'correlation spectroscopy' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.08323

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