Model for triplet state engineering in organic light emitting diodes.

  title={Model for triplet state engineering in organic light emitting diodes.},
  author={Suryoday Prodhan and Zolt{\'a}n G. Soos and Sheela K. Ramasesha},
  journal={The Journal of chemical physics},
  volume={140 21},
Engineering the position of the lowest triplet state (T1) relative to the first excited singlet state (S1) is of great importance in improving the efficiencies of organic light emitting diodes and organic photovoltaic cells. We have carried out model exact calculations of substituted polyene chains to understand the factors that affect the energy gap between S1 and T1. The factors studied are backbone dimerisation, different donor-acceptor substitutions, and twisted geometry. The largest system… 
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