X-ray photoelectron spectroscopic studies of some polyvinylpyridine. Acceptor complexes

Abstract

The charge-transfer (CT) interactions between poly-2-vinylpyridine and poly-4-vinylpyridine and various electron acceptors, such as I2, Br2 and 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), were studied by x-ray photoelectron spectroscopy (XPS). The CT interactions involving Br2 and DDQ proceeded further than the formation of pure molecular complexes and resulted in new adducts. Most of the iodine in the polymer-I2 complexes was found to be removable under reduced pressure. XPS data also revealed that the steric hindrance associated with the position of the pyridinium nitrogen has a marked effect on the extent of CT interactions in the DDQ, but not the halogen, complexes.