Cross-Peaks in Simple 2D NMR Experiments from Chemical Exchange of Transverse Magnetization

11 March 2019, Version 1
This content is a preprint and has not undergone peer review at the time of posting.

Abstract

Two-dimensional correlation measurements such as COSY, NOESY, HMQC and HSQC experiments are central to small molecule and biomolecular NMR spectroscopy, and commonly form the basis of more complex experiments designed to study chemical exchange occurring during additional mixing periods. However, exchange occurring during chemical shift evolution periods can also influence the appearance of such spectra. While this is often exploited through one-dimensional lineshape analysis ('dynamic NMR'), the analysis of exchange across multiple chemical shift evolution periods has received less attention. Here we report that chemical exchange-induced cross-peaks can arise in even the simplest two-dimensional NMR experiments. These cross-peaks can have highly distorted phases that contain rich information about the underlying exchange process. The quantitative analysis of such peaks, from a single 2D spectrum, can provide a highly accurate characterization of underlying exchange processes.

Keywords

chemical exchange
Two-dimensional NMR spectroscopy
lineshape analysis
dynamic NMR
nuclear magnetic resonance
NOESY
COSY
HSQC
HMQC

Supplementary materials

Title
Description
Actions
Title
Supporting Information
Description
Actions
Title
movie-S1
Description
Actions
Title
movie-S2
Description
Actions

Comments

Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.