2008/09/10 by Satoshi Miyashita, Kenji Yonemitsu · 1 citation
Chemistry · Materials Science · Physics and Astronomy · #Electronic and Structural Properties of Oxides #Organic and Molecular Conductors Research #Organometallic Compounds Synthesis and Characterization #cond-mat.str-el
paper · pdf · doi:10.1143/jpsj.77.094712
published as J. Phys. Soc. Jpn. 77, 094712 (2008) · 14 pages, 5 figures
openalex publication_date 2008/09/10 · arxiv created 2008/10/14 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The effects of spin and charge fluctuations and electron-phonon couplings on charge ordering in α-(BEDT-TTF)2I3 (BEDT-TTF=bis(ethylenedithio)-tetrathiafulvalence) are investigated theoretically for an anisotropic triangular lattice at 3/4 filling. By the exact-diagonalization method, we have calculated the hole density distributions and the modulations of transfer integrals from high-temperature values as a function of electron-phonon coupling strength. The results clearly show that the lattice effect on α-(BEDT-TTF)2I3 is weak compared with that on θ-(BEDT-TTF)2RbZn(SCN)4, as previously found by experiments. This finding, which is also consistent with recent mean-field results, is systematically explained by strong-coupling perturbation theory; the effects of spin fluctuations are partially canceled by charge fluctuations in α-(BEDT-TTF)2I3.