Metal-insulator transition in PF6 doped polypyrrole: interchain charge transfer versus electronic correlation

H. C. F. Martens; H. B. Brom; R. Menon

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arXiv · cond-mat/0101178

Metal-insulator transition in PF6 doped polypyrrole: interchain charge transfer versus electronic correlation

H. C. F. Martens·H. B. Brom·R. Menon

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Abstract

We performed dielectric spectroscopy on polypyrrole near the metal-insulator transition (MIT) down to 2 K. We evaluate the dependence of the plasma frequency and the scattering time (t) on the distance to the MIT, characterized by the Fermi-level relative to the band-edge of extended states, E_F-E_c. Especially the strong decrease of t with increasing E_F-E_c is in conflict with the usually applied models for the MIT. Although morphology and disorder are important, the MIT is Mott-Hubbard-like being dominated by the competition of interchain charge transfer and electronic correlation.

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H. C. F. Martens, H. B. Brom, R. Menon. 2001-01-12. Metal-insulator transition in PF6 doped polypyrrole: interchain charge transfer versus electronic correlation. https://arxiv.org/abs/cond-mat/0101178

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