Author/Authors :
Hatsui، نويسنده , , Takaki and Okamoto، نويسنده , , Kaoru and Yokoyama، نويسنده , , Toshihiko and Kitajima، نويسنده , , Yoshinori and Tanaka، نويسنده , , Hisashi and Ojima، نويسنده , , Emiko and Kobayashi، نويسنده , , Akiko and Ohta، نويسنده , , Toshiaki، نويسنده ,
Abstract :
High-resolution linearly polarized S K-edge X-ray absorption spectra for charge-transfer salts, λ-(BETS)2GaCl4 and β-(BEDT-TTF)2PF6 (BETS: bis(ethylenedithio)tetraselenafulvalene; BEDT-TTF: bis(ethylenedithiolo)tetrathiafulvalene) have been measured using undulator radiation. For both the compounds, weak bands below the most intense σ∗ transition are found. These characteristic bands are absent for the corresponding neutral compounds, BETS and BEDT-TTF. They are assigned to the transition to the highest occupied molecular orbital based on linear polarization dependence. These bands are proposed as a novel probe for determination of the hole concentration in the charge-transfer salts containing BETS and BEDT-TTF analogues.
