Ramasesha, S and Anusooya, Y and Pati, Swapan K and Tandon, Kunj S (1997) Symmetrized DMRG studies of low-energy electronic states of poly-para-phenylene (PPP) and poly-para-phenylenevinylene (PPV) systems. In: Conference on Optical Probes of Conjugated Polymers, Monday 28 July 1997, San Diego, CA, USA.Full text not available from this repository.
Symmetrized DMRG calculations on long oligomers of poly- para-phenylene (PPP) and poly-para-phenylene vinylene (PPV) systems within a `U-V' model have been carried out to obtain the one-photon, two-photon and singlet-triplet gaps in these systems. The extrapolated gaps (in eV) are 2.89, 3.76 and 2.72 in PPP and 3.01, 3.61 and 2.23 in PPV for the one- photon, two-photon and spin gaps respectively. By studying doped systems, we have obtained the exciton binding energies. The larger exciton binding energies, compared to strongly dimerized linear chains emphasizes the role of topology in these polymers. Bond orders, charge and spin correlations in the low-lying states bring out the similarities between the lowest one-photon, the lowest triplet and the lowest bipolaronic states in these systems. The two-photon state bond orders show evidence for strong localization of this excitation in both PPP and PPV systems.
|Item Type:||Conference Paper|
|Additional Information:||Copyright of this article belongs to SPIE--The International Society for Optical Engineering.|
|Date Deposited:||16 Mar 2012 07:25|
|Last Modified:||16 Mar 2012 07:25|
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