Charge-ordering in $\theta $-(BEDT-TTF)$_{2}$MM$^\prime $ (SCN)$_{4}$ [ M = Cs, Rb, Tl, M$^\prime $ = Zn, Co]

K. Suzuki; K. Yamamoto; M. Uruichi; K. Yakushi

doi:doi:10.1051/jp4:2004114089

Issue		J. Phys. IV France Volume 114, April 2004


Page(s)		379 - 381
DOI		https://doi.org/10.1051/jp4:2004114089

J. Phys. IV France 114 (2004) 379
DOI: 10.1051/jp4:2004114089

Charge-ordering in $\theta$ -(BEDT-TTF) ₂MM $^\prime$ (SCN) ₄ [ M = Cs, Rb, Tl, M $^\prime$ = Zn, Co]

K. Suzuki^{1, 1}, K. Yamamoto¹, M. Uruichi¹ and K. Yakushi¹

¹ The Graduate University for Advanced Studies and Institute for Molecular Science, Nishigonaka, Myodaiji-cho, Okazaki, Aichi, 444-8585, Japan

Abstract
Vibrational spectra, x-ray scattering and electrical resistivity of $\theta$ -(BEDT-TTF) ₂MM $^\prime$ (SCN) ₄, [ M = Cs, Rb, Tl, M $^\prime$ = Zn, Co] were measured in various temperature ranges. Vibrational spectra with the aid of x-ray scattering manifested charge disproportionation and charge ordering in their low-temperature phases. Except $\theta$ -(BEDT-TTF) ₂CsM $^\prime$ (SCN) ₄, the orthorhombic form provided a horizontal stripe. On the other hand, monoclinic $\theta$ -(BEDT-TTF) ₂TlZn(SCN) ₄ provided a diagonal stripe. The electronic state of the high-temperature phase is discussed based on the line shape of the Raman spectrum. Key words. Charge-ordering, BEDT-TTF, Raman spectroscopy, infrared spectroscopy.

Charge-ordering in -(BEDT-TTF) 2MM (SCN) 4 [ M = Cs, Rb, Tl, M = Zn, Co]

Charge-ordering in $\theta$ -(BEDT-TTF) ₂MM $^\prime$ (SCN) ₄ [ M = Cs, Rb, Tl, M $^\prime$ = Zn, Co]