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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Triplet energies of pi-conjugated polymers
A P Monkman1, H D Burrows, L J Hartwell
1Department of Physics, University of Durham, Durham, United Kingdom.
Abstract:
Using pulse radiolysis and triplet energy transfer has enabled us to measure the triplet energies in a broad range of different pi-conjugated polymers. In all cases we find that the 1 (3)B(u) is of order 0.6 to 1 eV below the 1 (1)B(u), indicative of localized triplet states with strong electron-electron correlation. We also observe that the 1 (1)A(g)-1 (3)B(u) gap decreases linearly as the 1 (1)A(g)-1 (1)B(u) gap decreases even though polymers with very different structure have been studied. This surprising result suggests that polymers with singlet gap <1.3 eV will have a triplet ground state.
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