liu.seSearch for publications in DiVA
Endre søk
Begrens søket
1 - 14 of 14
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Barta, P.
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Dannetun, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Stafström, Sven
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Zagórska, M.
    Department of Chemistry, Technical University of Warsaw, PL‐00 664 Warsaw, Poland.
    Pron, A.
    Department of Material Science and Ceramics, Academy of Mining and Metallurgy, PL‐30 059 Kraków, Poland.
    Temperature evolution of the electronic band structure of the undoped and doped regioregular analog of poly(3‐alkylthiophenes): A spectroscopic and theoretical study1994Inngår i: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 100, nr 2, s. 1731-1741Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The undoped and ferric chloride p‐doped ‘‘head‐to‐head’’ ‘‘tail‐to‐tail’’ analog of poly(3‐decylthiophene) obtained from substituted bithiophenes, i.e., poly(4,4’didecyl‐2,2’bithiophene)‐PDDBT has been investigated. The samples were studied by means of ultraviolet photoelectron spectroscopy,optical absorption measurements, and polymerbands structure calculations. Experiments were carried out at different temperatures between 100 °C and −180 °C. The results indicate that PDDBT is nonplanar in the undoped state. No temperature effects have been observed in the π‐electron properties. In the doped state, however, lowering of the temperature results in an increase of the system planarity that modifies the electronic band structure. This effect has been shown to be fully reversible with temperature.

  • 2.
    Bröms, P.
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Xing, K. Z.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Salaneck, William R.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Dannetun, Per
    Groupe de Physique des Solides, Tour 23-2, place Jussieu, F-752 51 Paris Cedex 05, France.
    Cornil, J.
    Service de Chimie des Matériaux Nouveaux, Université de Mons-Hainaut, B-7000 Mons, Belgium.
    Santos, D.A. dos
    Service de Chimie des Matériaux Nouveaux, Université de Mons-Hainaut, B-7000 Mons, Belgium.
    Brédas, J. L.
    Service de Chimie des Matériaux Nouveaux, Université de Mons-Hainaut, B-7000 Mons, Belgium.
    Moratti, S. C.
    University Chemical Laboratory, University of Cambridge, Cambridge CB2 1EW, UK.
    Holmes, A. B.
    University Chemical Laboratory, University of Cambridge, Cambridge CB2 1EW, UK.
    Friend, R. H.
    Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK.
    Optical absorption studies of sodium doped poly(cyanoterephthalylidene)1994Inngår i: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 67, nr 1-3, s. 93-96Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effects of doping poly(cyanoterephthalylidene) with sodium in ultrahighvacuum been studied by optical absorption spectroscopy. Upon doping, new optical transitions are observed within the bandgap; the characteristics of these transitions are consistent with the formation of bipolarons. The optical absorption results are confirmed by direct measurements of the doping-induced gap states using ultraviolet photoelectron spectroscopy.

  • 3.
    Dannetun, Per
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Fauquet, C.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Kaerijama, K.
    National Institute of Materials and Chemical Research, Tsukuba, Ibaraki 305, Japan.
    Sonoda, Y.
    National Institute of Materials and Chemical Research, Tsukuba, Ibaraki 305, Japan.
    Lazzaroni, R.
    Service de Chimie des Matériaux Nouveaux, Université de Mons-Hainaut, B-7000 Mons, Belgium.
    Brédas, J. L.
    Service de Chimie des Matériaux Nouveaux, Université de Mons-Hainaut, B-7000 Mons, Belgium.
    Salaneck, William R.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Interface formation between poly(2,5-diheptyl-p-phenylenevinylene) and calcium: implications for light-emitting diodes1994Inngår i: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 67, nr 1-3, s. 133-136Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The early stages of metal/polymer interface formation between calcium and poly(2,5-diheptyl-p-phenylenevinylene) (PDHPV) have been studied using both X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy. Charge transfer is observed from the metal atoms to the polymer; as a result the calcium atoms at the interface are ionic, and negative bipolarons appear as the charge-carrying species on the polymer chains. This n-type doping of PDHPV by calcium leads to the appearance of new electronic states in the polymer bandgap. The calcium atoms appear to diffuse into the near surface region of the polymer, rather than forming a well-defined overlayer on the organic films.

  • 4.
    Dannetun, Per
    et al.
    Groupe de Physique des Solides, Tour 23-2, place Jussieu, 752 51 Paris Cedex 05, France.
    Lögdlund, Michael
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Fauquet, C.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Beljonne, D.
    Service de Chimie des Matériaux Nouveaux, Université de Mons-Hainaut, place du Parc 20, B-7000 Mons, Belgium.
    Brédas, J. L.
    Service de Chimie des Matériaux Nouveaux, Université de Mons-Hainaut, place du Parc 20, B-7000 Mons, Belgium.
    Bässler, H.
    Fachbereich Physikalische Chemie und Zentrum für Materialwissenschaften der Phillips-Universität, Hans-Meerwein-Strasse, W-3550 Marburg, Germany.
    Salaneck, William R.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    The evolution of charge-induced gap states in degenerate and non-degenerate conjugated molecules and polymers as studied by photoelectron spectroscopy1994Inngår i: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 67, nr 1, s. 81-86Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We report the results of ultraviolet photoelectron spectroscopy (UPS) studies of the interaction between sodium and conjugated systems for a series of diphenylpolyees and diffrent oligomers of poly(p-phenylenevinylene) (PPV). The diphenylpolyenes include molecules containing two (i.e., stilbene) to 14 carbon atoms in the polyene part; stilbene itself can also be considered as a phenyl-capped monomer of PPV. Furthermore, a PPV oligomer with three phenylene units, as well as PPV itself, has been studied. The experimental results are interpreted with the help of quantum-chemical calculations using the Hartree-Fock semi-empirical Austin Model 1 (AM1) and valence-effective Hamiltonian (VEH) methods. An important result is that all the systems react strongly with sodium; at high doping levels two new doping-induced states are detected above the valence band edge of the pristine material. In the case of saturation-doped diphenylpolyenes (i.e., two sodiums per molecule), the new states can be discussed in terms of soliton-antisoliton pairs confined within the polyene part of the molecules; in contrast, the self-localized states induced in PPV and its oligomers have to be referred to as bipolarons.

  • 5.
    Dannetun, Per
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Lögdlund, Michael
    Service de Chimie des Matériaux Nouveaux, Université de Mons‐Hainaut, Place du Parc 20, B‐7000 Mons, Belgium.
    Fredriksson, C.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Lazzaroni, R.
    Service de Chimie des Matériaux Nouveaux, Université de Mons‐Hainaut, Place du Parc 20, B‐7000 Mons, Belgium.
    Fauquet, C.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Stafström, Sven
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Spangler, C. W.
    Department of Chemistry, Northern Illinois University, Dekalb, Illinois 60115, USA.
    Bredás, J. L.
    Service de Chimie des Matériaux Nouveaux, Université de Mons‐Hainaut, Place du Parc 20, B‐7000 Mons, Belgium.
    Salaneck, William R.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Reactions of low work function metals Na, Al, and Ca on α,ω-€diphenyltetradecaheptaene. Implications for metal/polymer interfaces1994Inngår i: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 100, nr 9, s. 6765-6771Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The interactions between different low work function metals aluminium,calcium and sodium, and α,ω‐diphenyltetradecaheptaene, a model molecule for certain conjugated polymers, have been investigated using both x‐ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy. The spectra are interpreted with the help of the results of quantum chemical calculations performed within the local spin density (LSD) approximation methodology. The metals are found to interact with the conjugated system in very different ways. Aluminium forms a covalent bond, which strongly modifies the π‐electronic structure of the conjugated molecule, while both the sodium and the calcium atoms act as doping agents, inducing new states in the otherwise forbidden bandgap. These new gap states can be viewed as a soliton–antisoliton pair for the Na/DP7 and a bipolaronic‐like defect for Ca/DP7.

  • 6.
    Dannetun, Per
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Lögdlund, Michael
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Salaneck, William R.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Fredriksson, C.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Stafström, Sven
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Holmes, A. B.
    Cavendish Laboratory , University of Cambridge Cambridge , CB3 OHE, England.
    Brown, A.
    Cavendish Laboratory , University of Cambridge Cambridge , CB3 OHE, England.
    Graham, S.
    Cavendish Laboratory , University of Cambridge Cambridge , CB3 OHE, England.
    Friend, R. H.
    Cavendish Laboratory , University of Cambridge Cambridge , CB3 OHE, England.
    Lhost, O.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    New Results on Metal-Polymer Interfaces1993Inngår i: Molecular Crystals and Liquid Crystals, ISSN 1542-1406, E-ISSN 1563-5287, Vol. 228, nr 1, s. 43-48Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    New results on studies of the early stages of formation of the aluminum-poly(p-phenylenevinylene) interface are presented.

  • 7.
    Dannetun, Per
    et al.
    Groupe de Physique des Solides, Unité associée au CNRS 040017, Universités Paris 7 et Paris 6, Tour 23, 2 Place Jussieu, France.
    Schott, M
    Groupe de Physique des Solides, Unité associée au CNRS 040017, Universités Paris 7 et Paris 6, Tour 23, 2 Place Jussieu, France.
    Vilar, M.Rei
    Laboratoire de Spectrochimie Infrarouge et Raman (CNRS), Thiais, France.
    High-resolution electron energy loss spectroscopy of thin crystalline highly oriented films of poly(tetrafluoroethylene)1996Inngår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 286, nr 1-2, s. 321-329Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    High-resolution electron energy loss spectroscopy (HREELS) spectra of highly oriented films of poly(tetrafluoroethylene) (PTFE) are reported. With one exception, all peaks in the spectra correspond to IR active vibrations. They are well resolved, and with a remarkably high intensity, more than two orders of magnitude greater than we have observed on any other polymer in HREELS. The angular distributions of the elastic peak, and of the vibrational peaks are very narrow, which indicates both a well ordered system and a dipolar scattering behaviour. No evidence of amorphous regions in these films is found. A Raman active mode can be observed in off-specular geometry, using an incident electron beam coplanar with the PTFE fibers direction. This corresponds to resonance excitation of a transient negative ion state, with a maximum cross-section at an incident electron kinetic energy of about 4 eV.

  • 8.
    Fauquet, C.
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Dannetun, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Fredriksson, C.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Stafström, Sven
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Bourée, J. E.
    CNRS, Laboratoire de Meudon, Meudon, France.
    Brillaud, P.
    SMI Organometallics Division, 13 000 Marseille, France.
    Bouanah, N.
    SMI Organometallics Division, 13 000 Marseille, France.
    Salaneck, William R.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Electronic structure of trimethylamine alane in the solid state1995Inngår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 235, nr 5-6, s. 528-534Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The chemical and electronic structure of ultrathin molecular films of trimethylamine alane (TMAA), condensed in UHV at − 100°C, have been studied in the solid state, using both X-ray and ultraviolet photoelectron spectroscopy. The results are analyzed with the help of quantum chemical calculations at the ab initio Hartree-Fock 6-31G∗ level. Based upon the good agreement between theory and experimental, it is determined that clean, oxygen-free, condensed molecular solid films consist of the 2:1 adduct of TMAA, which was previously uncertain. In addition, based upon the electronic structure results, it is clear that the mechanism of the photodecomposition of TMAA can be explained in terms of the wavefunction of electrons photoexcited into the first unoccupied molecular orbital.

  • 9.
    Lazzaroni, R.
    et al.
    Service de Chimie des Matériaux Nouveaux, Département des Matériaux et Procédés, Université de Mons-Hainaut, Mons, Belgium.
    Brédas, J. L.
    Service de Chimie des Matériaux Nouveaux, Département des Matériaux et Procédés, Université de Mons-Hainaut, Mons, Belgium.
    Dannetun, Per
    Service de Chimie des Matériaux Nouveaux, Département des Matériaux et Procédés, Université de Mons-Hainaut, Mons, Belgium.
    Fredriksson, C.
    Service de Chimie des Matériaux Nouveaux, Département des Matériaux et Procédés, Université de Mons-Hainaut, Mons, Belgium.
    Stafström, Sven
    Service de Chimie des Matériaux Nouveaux, Département des Matériaux et Procédés, Université de Mons-Hainaut, Mons, Belgium.
    Salaneck, William R.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    The chemical and electronic structure of the interface between aluminum and conjugated polymers1994Inngår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 39, nr 2, s. 235-244Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The chemical and electronic structure of the interface between aluminum and several proto-typical conjugated systems is investigated with a combined experimental and theoretical approach. The experiments consists of following the evolution of the polymer surface during the early stages of aluminum deposition, with X-ray and Ultraviolet Photoelectron Spectroscopies (XPS, UPS). In parallel, quantum chemical calculations are performed on model oligomer systems interacting with isolated Al atoms. Aluminum is found to interact strongly with the polymer chain. New covalent Al-carbon bonds are formed along the polymer backbone; the chain geometry is deeply modified and the π electron conjugation can be dramatically reduced.

  • 10.
    Lazzaroni, R.
    et al.
    Service de Chimie des Matériaux Nouveaux Centre de Recherche en Electronique et Photonique Moléculaires Université de Mons-Hainaut, Mons, Belgium.
    Lögdlund, Michael
    Service de Chimie des Matériaux Nouveaux Centre de Recherche en Electronique et Photonique Moléculaires Université de Mons-Hainaut, Mons, Belgium.
    Calderone, A.
    Service de Chimie des Matériaux Nouveaux Centre de Recherche en Electronique et Photonique Moléculaires Université de Mons-Hainaut, Mons, Belgium.
    Brédas, J. L.
    Service de Chimie des Matériaux Nouveaux Centre de Recherche en Electronique et Photonique Moléculaires Université de Mons-Hainaut, Mons, Belgium.
    Dannetun, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Fauquet, C.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Fredriksson, C.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Stafström, Sven
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Salaneck, William R.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Chemical and electronic aspects of metal/conjugated polymer interfaces: Implications for electronic devices1995Inngår i: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 71, nr 1-3, s. 2159-2162Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The chemical nature and the electronic structure of metal/conjugated polymer interfaces are investigated in the context of polymer-based light-emitting diodes. We consider the interaction of low-workfunction metals (Al, Ca) with the surface of conjugated polymers or model oligomer molecules with a combined experimental and theoretical approach. The early stages of the interface formation are followed with X-ray and ultraviolet photoelectron spectroscopies and the experimental data are compared to the results of quantum chemical calculations. The reactions of Al and Ca with the organic surface are found to be fundamentally different: while the former forms new covalent bonds onto the polymer backbone, the latter tends to dope the conjugated system. Both types of reaction are expected to modify drastically the electronic properties of the polymer semiconductor.

  • 11.
    Lögdlund, Michael
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan. Service de Chimie des Matériaux Nouveaux, Centre de Recherche en Electronique et Photonique Moléculaires, Université de Mons-Hainaut, Mons, Belgium.
    Dannetun, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Fredriksson, C.
    Ecole Polytechnique de Montréal, Centre de Recherche Appliquée Sur les Polymères (CRASP), Département de Génie Chimique, Case Postale 6079, Succursale A, Montréal, Québec, H3C 3A7 Canada.
    Salaneck, William R.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Brédas, J. L.
    Service de Chimie des Matériaux Nouveaux, Centre de Recherche en Electronique et Photonique Moléculaires, Université de Mons-Hainaut, Mons, Belgium.
    Theoretical and experimental studies of the interaction between sodium and oligothiophenes1996Inngår i: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 53, nr 24, s. 16327-16333Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Quantum-chemical calculations and ultraviolet photoelectron spectroscopy (UPS) measurements have been performed in order to study the interaction between sodium and oligothiophenes, with a focus on the origin of experimentally observed relaxation energy effects in alkali-metal-doped conjugated molecules. Upon doping of a -sexithienylene (α-6T) with sodium atoms, (1) a broad feature appears in the valence band, in an energy region corresponding to the band gap in pristine α-6T, and (2) certain structural features in the valence band shift towards lower binding energies in the doped material. In particular, upon doping, a structural peak related to electronic levels mainly localized to the sulfur and b-carbon atoms destabilizes to an energy corresponding to that of the valence-band edge in pristine α-6T. The results of ab initio Hartree-Fock and local-spin-density calculations on α-trithienylene and bithiophene are consistent with the experimental data, and allow for an assignment of these destabilization effects in terms of initial-state relaxations. We stress that similar destabi-lization effects, reported for other alkali-metal-doped conjugated systems, had previously been proposed to be associated with final-state electronic screening, i.e., a dynamic artifact within the UPS measurements; this is in contradiction to the results of our ab initio theoretical studies. Our present results show that all structural features in the UPS data are contained in the results of sufficiently complete quantum chemical calculations.

  • 12.
    Lögdlund, Michael
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan. Service de Chimie des Matériaux Nouveaux, Centre de Recherche en Electronique et Photonique Moléculaires, Université de Mons-Hainaut, Mons, Belgium.
    Dannetun, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan. Groupe de Physique des Solides, place Jussieu, 75251 Paris Cedex 05, France.
    Fredriksson, C.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Salaneck, William R.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Brédas, J. L.
    Service de Chimie des Matériaux Nouveaux, Centre de Recherche en Electronique et Photonique Moléculaires, Université de Mons-Hainaut, Mons, Belgium.
    Theoretical study of the interaction between sodium and oligomers of poly(p-phenylenevinylene) and poly(p-phenylene)1994Inngår i: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 67, nr 1-3, s. 141-145Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The semi-empirical Austin Model 1 and the non-empirical pseudo-potential valence effective Hamiltonian (VEH) methods as well as the local spin density (LSD) approximation technique have been applied to the investigation of the doping-induced electronic and geometrical changes in some conjugated molecules related to poly(p-phenylene) and poly(p-phenylenevinylene) (PPV): biphenyl, stilbene and a phenyl-capped dimer of PPV. The theoretical results are compared with experimental valence band spectra, as recorded by ultraviolet photoelectron spectroscopy (UPS). The experimental UPS studies show that two ingap states are detected upon doping with alkali metals. The energy splitting between the two in-gap states increases as the molecule size decreases. The results of the LSD calculations agree very well with the experimental results, while the VEH method overestimates the energy splitting for the small molecules. The LSD modelling also indicates a destabilization of several high binding energy valence levels, due to the presence of counter-ions, in agreement with experiment.

  • 13.
    Salaneck, William R.
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Dannetun, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Lögdlund, Michael
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Photoelectron Spectroscopy: A Basic Tool for the Study of Molecular Materials1992Inngår i: Nanostructures Based on Molecular Materials / [ed] W. Gopel and Ch Ziegler, Weinhem: Vch Pub , 1992, s. 329-348Kapittel i bok, del av antologi (Fagfellevurdert)
  • 14.
    Uvdal, Kajsa
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Lögdlund, M.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Dannetun, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Bertilsson, L.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Stafström, Sven
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Salaneck, William R.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    MacDiarmid, A. G.
    Department of Chemistry, University of Pennsylvania, Philadelphia, USA.
    Ray, A.
    Chemistry, University of Pennsylvania, Philadelphia, USA.
    Scherr, E. M.
    Chemistry, University of Pennsylvania, Philadelphia, USA.
    Hjertberg, T.
    Department of Polymer Technology, Chalmers University, Göteborg, Sweden.
    Epstein, A. J.
    Department of Physics, The Ohio State University, Columbus, OH, USA.
    Vapor deposited polyaniline1989Inngår i: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 29, nr 1, s. 451-456Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have prepared thin films of polyaniline (emeraldine base) by an open boat evaporation process. These vapor-deposited films have a higher molecular weight than expected from a vapor deposition process, indicating a post deposition chemical process. The films have optical properties very similar to, but not identical to, these of “conventional” emeraldine. After treatment with protonic acid, the films exhibit an electrical conductivity of up to about 10% of that of conventional emeraldine salt.

1 - 14 of 14
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf