| 1. |
- Bröms, P., et al.
(författare)
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Optical absorption studies of sodium doped poly(cyanoterephthalylidene)
- 1994
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Ingår i: Synthetic metals. - : Elsevier. - 0379-6779 .- 1879-3290. ; 67:1-3, s. 93-96
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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| 2. |
- Dannetun, Per, et al.
(författare)
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New Results on Metal-Polymer Interfaces
- 1993
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Ingår i: Molecular Crystals and Liquid Crystals. - : Taylor & Francis. - 1542-1406 .- 1563-5287. ; 228:1, s. 43-48
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Tidskriftsartikel (refereegranskat)abstract
- New results on studies of the early stages of formation of the aluminum-poly(p-phenylenevinylene) interface are presented.
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| 3. |
- Dannetun, Per, et al.
(författare)
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Proceedings of the International Conference on Science and Technology of Synthetic Metals The chemical and electronic structure of the interface between aluminum and conjugated polymers or molecules
- 1993
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Ingår i: Synthetic metals. - : Elsevier. - 0379-6779 .- 1879-3290. ; 55:1, s. 212-217
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Tidskriftsartikel (refereegranskat)abstract
- The interaction between aluminum and α-ω-diphenyltetradecaheptaenee (DP7), α-sexithienyl (6T), and poly(p-phenylenevinylene) (PPV), respectively have been studied using both X-ray Photoelectron Spectroscopy (XPS) and Ultraviolet Photoelectron Spectroscopy (UPS). The UPS valence band spectra, are interpreted with the help of quantum chemical calculations based upon Modified Neglect of Diatomic Overlap (MNDO), Valence Effective Hamitonian (VEH) and ab initio Hartree-Fock methods. DP7 is a model molecule for polyacetylene, while 6T is a model molecule (an oligomer) of polythiophene. The results indicate that aluminum reacts strongly with the surfaces of all of the materials studied. The π-electronic structure of each material was strongly modified. Furthermore, aluminum reacts preferentially with the polyene partof DP7, with the vinylene part of PPV, and with the α-carbons of the thiophene nits of 6T.
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| 4. |
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| 5. |
- Lögdlund, Michael, et al.
(författare)
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The electronic structure of α,ω-diphenyltetradecaheptaene, a model molecule for polyacetylene, as studied by photoelectron spectroscopy
- 1992
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Ingår i: Synthetic metals. - : Elsevier. - 0379-6779 .- 1879-3290. ; 51:1, s. 187-195
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Tidskriftsartikel (refereegranskat)abstract
- The advantages of using model systems for spectroscopic studies of conjugated polymers and interface formation, as well as for charge-induced electronic and geometric structural changes, are discussed. The electronic structure of a diphenylpolyene, α,ω-diphenyltetradecaheptaene, or DP7, is an example of a model molecular system studied using X-ray and Ultraviolet Photoelectron Spectroscopy, XPS, and UPS. The spectra are interpreted with the help of the results from MNDO, VEH and INDO/S-CI quantum chemical calculations. The frontier orbitals of DP7 are localized mostly on the polyene chain portion of the molecule, resulting in a high degree of separation of the phenyl and polyene parts of the π-system. The INDO calculations show two regions of shake-up features corresponding to a benzene-like part and a polyene-like part. The most important individual shake-up transitions, which contribute to the two observed shake-up spectral features, involve one-electron redistributions separable into contributions from the polyene chain and from the phenyl groups. The analysis indicates the extent to which many chemical and electronic properties of DP7 are expected to be similar to those of (at least short chain) trans-polyacetylene.
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| 6. |
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| 7. |
- Smith, R. J., et al.
(författare)
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Clinical diagnosis of the Usher syndromes : Usher Syndrome Consortium
- 1994
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Ingår i: American Journal of Medical Genetics. - : Wiley. - 0148-7299 .- 1096-8628. ; 50:1, s. 32-38
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Tidskriftsartikel (refereegranskat)abstract
- The Usher syndromes are genetically distinct disorders which share specific phenotypic characteristics. This paper describes a set of clinical criteria recommended for the diagnosis of Usher syndrome type I and Usher syndrome type II. These criteria have been adopted by the Usher Syndrome Consortium and are used in studies reported by members of this Consortium.
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