Association constants of organic charge-transfer complexes derived from optical and from nuclear magnetic resonance chemical shift measurements; the presence of termolecular complexes

Abstract

Anomalous association constants have been obtained from the kinetics of the decay of substituted p-benzoquinone–hexamethylbenzene systems. The apparent association constants for several systems have been shown to be dependent on the concentration of the component in excess. It is suggested that these observations are the result of the formation of termolecular complexes as well as of the anticipated 1:1 complexes. Association constants for the double equilibria have been evaluated in several cases.