The occurrence of a large
intramolecularcharge separation in the singlet
excited state of polyenes and their derivatives twisted about a double bond. Non-symmetrical substitution
or geometrical distortion is effective in polarizing the system. An example is the
stabilization of the zwitterionic structure of 90° twisted ethene with one
methylene group pyramidalized:
Source:
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by
A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997).
XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic,
J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8.
https://doi.org/10.1351/goldbook.
