Measurement principle of spectroscopy in which spectra are recorded at different magnitudes of an applied external perturbation of the sample and are processed to yield a 2-D correlation spectrum.
Notes:
The external perturbation may be time dependent (chemical reactions, physical relaxation processes), or static (temperature change, concentration change).
Source: PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 677 (https://doi.org/10.1515/pac-2019-0203)