The charge ordered state and the possible 2kF-CDW state with fermi surface nesting in organic conductor θ-(BEDT-TTF)2MM′(SCN)4 (MM′ = RbZn, CsCo)

M. Watanabe, Y. Noda, Y. Nogami, K. Oshima, H. Mori

Research output: Contribution to journalConference article

1 Citation (Scopus)

Abstract

Two-dimensional organic conductor θ-(BEDT-TTF)2RbZn(SCN)4 and θ-(BEDT-TTF)2CsCo(SCN)4 were investigated by X-ray diffraction measurements. Both salts exhibit an isostructural crystal structure at room temperature (RT). However, the RbZn salt undergoes a metal-insulator transition associated with superlattice formation of 2c. The charge ordered state below TMI was observed by crystal structure analysis taking into account of the superlattice. This modulation of 2c has no relation to the topology of the calculated Fermi surface nesting vector at all. Below TMI, the systematic deformations of BEDT-TTF molecular shape indicated charge disproportionation between BEDT-TTFs possibly caused by the electron correlation effect. On the other hand, in the CsCo salt, another incommensurate lattice modulation was found under high pressure of IGPa. This incommensurate modulation vector of (2/3 0 0.29) is in agreement with the nesting vector of Fermi surface under high pressure. In this system, it seems that small change caused by chemical substitution can vary the electronic state from the charge ordered state to the CDW state.

Original languageEnglish
Pages (from-to)Pr9/231-Pr9/232
JournalJournal De Physique. IV : JP
Volume12
Issue number9
Publication statusPublished - Nov 1 2002
EventInternational Workshop on Electronic Crystals - ECRYS 2002 - Saint Flour, France
Duration: Sep 2 2002Sep 7 2002

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'The charge ordered state and the possible 2k<sub>F</sub>-CDW state with fermi surface nesting in organic conductor θ-(BEDT-TTF)<sub>2</sub>MM′(SCN)<sub>4</sub> (MM′ = RbZn, CsCo)'. Together they form a unique fingerprint.

  • Cite this