EPR and 1H and 13C dynamic nuclear polarization studies of a molecularly doped polymer: bisphenol A polycarbonate doped with trianisylamine and trianisylaminium perchlorate.

We have investigated the EPR and DNP behavior of a molecularly doped polymer modeling those used to transport electronic charge in electrophotography. The EPR spectra show no evidence of the superexchange reported for a closely related system based on tri-p-tolylamine. The difference may be due to larger charge-transfer matrix elements in the latter system.

Spectroscopic studies of the metal complexes of ethylenediaminetetra-acetic acid in aqueous solution.

Aqueous solutions of the metal complexes of ethylenediaminetetra-acetic acid (EDTA) are widely used in analysis; though X-ray diffraction methods cannot be directly used for structural determination in solution, ultraviolet-visible region, vibrational and NMR spectroscopy studies demonstrate that the species in solution adopt a similar range of stereochemistries to those determined for the solid state. Thus a review of the spectroscopic properties of the solutions suggests that chelates are formed in which the denticity of EDTA varies from one to six and the co-ordination number about the metal from four to nine.

Structure and bonding in the metal complexes of ethylenediaminetetra-acetic acid.

The metal-ion complexes of ethylenediaminetetra-acetic acid (EDTA) find widespread use not only in analysis, but also in foodstuffs, pharmacy, and medicine. A review of the structures of the solid complexes illustrates the considerable variation in co-ordination number of the metal-ion, and the possible denticities of EDTA. These data are relevant to the solid-state properties and also to the structures of the complexes in solution, which cannot be directly determined.

Characteristic metal-halogen vibrational frequencies of complexes with bivalent metal halides.

Studies of the metal-halogen vibrational frequencies of complexes have been numerous and it is apparent that such frequencies are often characteristic of the structure and stoichiometry. The method, although generally applicable, is most valuable where neither ultraviolet spectra nor magnetic moments can be of assistance. The current literature is reviewed with the intention of facilitating the characterization of unknown materials derived from bivalent metal halides.