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The luminescence spectra of various polymers and solid-model compounds induced by 1-MeV electrons are reported and interpreted. The presence of enhanced triplet emission and absence of singlet emission from poly(p-xylene), poly(monochloro-p-xylene), and the model compound dibenzyl are interpreted on the basis of a molecular resonance model. Some triplet excimer and other long-wavelength (450–550-mμ) emission were also observed in these spectra. The spectra of the monomers p-xylene and 2-chloro-p-xylene consisted primarily of long-wavelength emission (400–600 mμ), while the spectra of frozen toluene and durene exhibited both neutral molecule singlet and the long-wavelength emission. Benzene exhibited only singlet, singlet excimer, triplet, and triplet excimer emission. The polymers poly(ethylene-2,6-naphthalene-dicarboxylate), poly(ethyleneterephthalate), and polysulfone emitted primarily from singlet and singlet excimer states. The model compounds for these polymers, dimethyl-2,6-naphthalenedicarboxylate, dimethylterephthalate, and methyl-p-toluenesulfonate exhibited varying amounts of singlet, triplet, excimer, and neutral or ionic radical emission.

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Oneelectron properties of several small molecules using near Hartree-Fock limit basis sets Basis set effects in Hartree-Fock studies on aromatic molecules: Hartree-Fock calculations of properties in benzene and hexafluorobenzeneThe half-projected Hartree-Fock (HPHF) method is examined with respect to its ability to obtain molecular correlation. describe molecular potential energy surfaces, and provide a one particle basis for more elaborate treatments. The equivalence, aside from questions of efficiency, of two different HPHF algorithms is demonstrated. The results of calculations on H,o, C 2 , N" and CH, indicate that the performance of the HPHF method, with spin projection in appropriate cases, is roughly equivalent to limited MCSCF treatments. In particular, (I) a small but important fraction of the correlation energy, (2) qualitatively correct potential energy surfaces, and (3) good one particle orbital bases are obtained.Let {aj} and {b/} be the sets of alpha-and beta-corre-5174