2007/03/26 by William Barford, Barford, William
Biochemistry, Genetics and Molecular Biology · Engineering · Neuroscience · Physics and Astronomy · #Advanced Fluorescence Microscopy Techniques #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Organic Electronics and Photovoltaics #Photoreceptor and optogenetics research #physics.chem-ph
paper · pdf · doi:10.48550/arxiv.physics/0703233
arxiv created 2007/03/26 · openalex publication_date 2007/03/26 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The line-dipole approximation for the evaluation of the exciton transfer integral, J, between conjugated polymer chains is rigorously justified. Using this approximation, as well as the plane-wave approximation for the exciton center-of-mass wavefunction, it is shown analytically that J ∼ L when the chain lengths are smaller than the separation between them, or J∼ L-1 when the chain lengths are larger than their separation, where L is the polymer length. Scaling relations are also obtained numerically for the more realistic standing-wave approximation for the exciton center-of-mass wavefunction, where it is found that for chain lengths larger than their separation J ∼ L-1.8 or J ∼ L-2, for parallel or collinear chains, respectively. These results have important implications for the photo-physics of conjugated polymers and self-assembled molecular systems, as the Davydov splitting in aggregates and the Förster transfer rate for exciton migration decreases with chain lengths larger than their separation. This latter result has obvious deleterious consequences for the performance of polymer photovoltaic devices.