push-pull conjugation

https://doi.org/10.1351/goldbook.08200
Feature of an extended conjugated \(\ce{\uppi\ system}\) bearing an electron donor group at one end and an electron acceptor group at the other end.
Source:
PAC, 2022, 94, 353. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 2021)) on page 490 [Terms] [Paper]