Premium
Magnetic coupling between two phenoxyl radicals attached to the phenyl rings of CIS ‐ and trans ‐stilbenes
Author(s) -
Mitsumori Teruyuki,
Koga Noboru,
Iwamura Hiizu
Publication year - 1994
Publication title -
journal of physical organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.325
H-Index - 66
eISSN - 1099-1395
pISSN - 0894-3230
DOI - 10.1002/poc.610070108
Subject(s) - chemistry , radical , chromophore , cis–trans isomerism , antiferromagnetism , steric effects , coupling (piping) , magnetic dipole–dipole interaction , dipole , electron paramagnetic resonance , inductive coupling , ferromagnetism , conjugated system , photochemistry , sign (mathematics) , crystallography , stereochemistry , molecular physics , nuclear magnetic resonance , condensed matter physics , organic chemistry , physics , mechanical engineering , engineering , polymer , mathematical analysis , mathematics , quantum mechanics
Magnetic coupling between two sterically protected phenoxyl radicals through the cis ‐ and trans ‐stilbene chromophores was studied by means of their EPR fine structures. While the zero‐field splitting parameters D , which are governed by the magnitude of dipolar coupling, were dependent on the geometrical isomerism, the sign of exchange coupling was independent of it and dictated by the topology of the π‐conjugated systems: ferromagnetic in o , m ‐isomers and antiferromagnetic in m , m '‐isomers.