| Numéro |
J. Phys. IV France
Volume 114, April 2004
|
|
|---|---|---|
| Page(s) | 87 - 90 | |
| DOI | https://doi.org/10.1051/jp4:2004114016 | |
J. Phys. IV France 114 (2004) 87
DOI: 10.1051/jp4:2004114016
Phase transition in the organic conductor (TTM-TTP)I 3 studied by infrared and Raman spectroscopies
R. Swietlik1, 2, 1, K. Yakushi2, K. Yamamoto2, T. Kawamoto3 and T. Mori31 Inst. Molec. Physics, Polish Academy of Sciences, ul. Smoluchowskiego 17, 60-179 Poznañ, Poland
2 Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
3 Depart. Organic and Polymeric Mater., Tokyo Instit. Technology, O-Okayama, Tokyo, Meguro 152-8552, Japan
Abstract
Polarised infrared reflectance (600-10000 cm
-1) as
well as Raman scattering spectra of the organic conductor (TTM-TTP)I
3
were investigated as a function of temperature, below and above the
metal-insulator phase transition at T=160 K. The IR electronic dispersion
was analysed in terms of a Lorentz model and optical transport parameters
were determined. The phase transition at 160 K has nearly no influence on IR
spectra. The Raman scattering was studied for different excitations
(
=514.5, 632.6 and 785 nm). Within the C=C stretching region
three Raman bands at 1436, 1453 and 1486 cm
-1 were found and assigned
to the three TTM-TTP modes of a
symmetry. Due to the phase transition
the band at 1486 cm
-1 splits into two lines at about 1487 and 1500
cm
-1. We relate this splitting to an asymmetric deformation of TTM-TTP.
Key words. TTM-TTP salt - organic metal - IR and Raman spectra -
phase transition.
© EDP Sciences 2004