Dispersion-induced insulator-to-metal transition in polyaniline
B. Wessling1 - D. Srinivasan2 - G. Rangarajan2 - T. Mietzner3 - W. Lennartz3
1 Ormecon Chemie (a subsidiary of Zipperling Kessler &
Co) Ammersbek, Germany
2 Department of Physics, Indian
Institute of Technology, Madras, India
3 II. Department of
Physics, University of Cologne, Germany
wessling@zipperling.do.uunet.de
Received 11 May 1999 and Received in final form 22 November 1999
Abstract
Melt dispersion processing--without solvents or "secondary
dopants''--pushes polyaniline reproducibly to the metallic side
of the IM transition, although the undispersed polyaniline is on
the insulator side. This is the first time that a conductive
polymer is found there without applying pressure. The transition
to the metallic state is associated with a decrease of the
C6-N-C6 angle from
to
.
PACS
71.30.+h Metal-insulator transitions and other electronic transitions
- 75.40.Cx Static properties (order parameter, static susceptibility, heat capacities,
critical exponents, etc.)
- 61.10.-i X-ray diffraction and scattering
Copyright EDP Sciences, Società Italiana di Fisica, Springer-Verlag
