title: Near-Edge X-ray Absorption Fine Structure Investigation of the Quasi-One-Dimensional Organic Conductor (TMTSF)2PF6.
abstract: We present high-resolution near-edge X-ray absorption fine structure (NEXAFS) measurements at the P L2/3edges, F K edge, C K edge, and Se M2/3edges of the quasi-one-dimensional (1D) conductor and superconductor (TMTSF)2PF6. NEXAFS allows probing the donor and acceptor moieties separately; spectra were recorded between room temperature (RT) and 30 K at normal incidence. Spectra taken around RT were also studied as a function of the angle (θ) between the electric field of the X-ray beam and the 1D conducting direction. In contrast with a previous study of the S L2/3-edges spectra in (TMTTF)2AsF6, the Se M2/3edges of (TMTSF)2PF6do not exhibit a well-resolved spectrum. Surprisingly, the C K-edge spectra contain three well-defined peaks exhibiting strong and nontrivial θ and temperature dependence. The nature of these peaks as well as those of the F K-edge spectra could be rationalized on the basis of first-principles DFT calculations. Despite the structural similarity, the NEXAFS spectra of (TMTSF)2PF6and (TMTTF)2AsF6exhibit important differences. In contrast with the case of (TMTTF)2AsF6, the F K-edge spectra of (TMTSF)2PF6do not change with temperature despite stronger donor-anion interactions. All these features reveal subtle differences in the electronic structure of the TMTSF and TMTTF families of salts.
authors.affiliation: Lund University , MAX IV Laboratory, 22100 Lund, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Medjanik
authors.affiliation: Institut für Physik, Johannes Gutenberg-Universität , 55099 Mainz, Germany.|Graduate School of Materials Science in Mainz, Johannes Gutenberg University Mainz , 55128 Mainz, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Chernenkaya
authors.affiliation: Institut für Physik, Johannes Gutenberg-Universität , 55099 Mainz, Germany.
authors.forename: X
authors.initials: X
authors.lastname: Kozina
authors.affiliation: Institut für Physik, Johannes Gutenberg-Universität , 55099 Mainz, Germany.
authors.forename: S A
authors.initials: SA
authors.lastname: Nepijko
authors.affiliation: Lund University , MAX IV Laboratory, 22100 Lund, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Öhrwall
authors.affiliation: Laboratoire de Physique des Solides, Université Paris-Sud , CNRS UMR 8502, 91405 Orsay, France.
authors.forename: P
authors.initials: P
authors.lastname: Foury-Leylekian
authors.affiliation: Departament de Ciència de Materials i Química Física and Institut de Química Teórica i Computacional (IQTCUB), Universitat de Barcelona , Martí i Franquès 1, 08028 Barcelona, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Alemany
authors.affiliation: Institut für Physik, Johannes Gutenberg-Universität , 55099 Mainz, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Schönhense
authors.affiliation: Institut de Ciència de Materials de Barcelona (ICMAB-CSIC) , Campus de la UAB, 08193 Bellaterra, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Canadell
authors.affiliation: Laboratoire de Physique des Solides, Université Paris-Sud , CNRS UMR 8502, 91405 Orsay, France.
authors.forename: J-P
authors.initials: JP
authors.lastname: Pouget