uu.seUppsala University Publications
Change search
Refine search result
3456789 251 - 300 of 613
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 251.
    Iribarne, F
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Paulino, M
    Tapia, O
    Hydride-transfer transition structure as a possible unifying redox step for describing the branched mechanism of glutathione reductase. Molecular-electronic antecedents2000In: THEORETICAL CHEMISTRY ACCOUNTS, ISSN 1432-881X, Vol. 103, no 6, p. 451-462Article in journal (Refereed)
    Abstract [en]

    For glutathione reductase (GR), a mammalian reduced nicotinamide adenine dinucleotide phosphate dependent flavoenzyme participating in free-radical detoxification pathways, we present a quantum chemical study addressing aspects of its electronic mechanism

  • 252.
    Iribarne, Fredricio
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Paulino, Margot
    Aguilera, Sara
    Murphy, Miguel
    Tapia, Orlando
    Docking and molecular dynamic studies at trypanothione reductase and glutathione reductase active sites2002In: J Mol Model, Vol. 8, p. 173-183Article in journal (Refereed)
  • 253.
    Itsenko, Oleksiy
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Norberg, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry, Quantum Chemistry.
    Rasmussen, Torben
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Långström, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry.
    Chatgilialoglu, Chryssostomos
    Radical Carbonylation with [11C]Carbon Monoxide Promoted by Oxygen-Centered Radicals: Experimental and DFT studies of the mechanism2007In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 129, no 29, p. 9020-9031Article in journal (Refereed)
    Abstract [en]

    Photoinitiated carbonylation of alkyl iodides with [11C]carbon monoxide (11C t1/2 = 20.4 min) is enhanced by ketones that have lowest-lying excited triplet state of nπ* character. For example, adding 5 mol % of acetophenone increases radiochemical yields from 3 to 59% in brief 6-min long reactions. Similar or higher yields were achieved by adding di-tert-butyl peroxide. Since radicaloid nπ* exited-state ketones and tert-butoxyl radicals have similar reactivity, the photosensitization proceeds most likely via a H-atom transfer mechanism rather than via energy transfer. We propose a mechanism that can account for the enhancement as well as for the formation of observed byproducts. The energy profile obtained by DFT calculations support the feasibility of the mechanism, and observed experimental differences in reactivity could be well rationalized by the calculated data. NBO calculations were performed to further analyze the obtained energetics. Various [carbonyl-11C]esters and some [carbonyl-11C]amides were synthesized in good radiochemical yields from primary and secondary alkyl iodides illustrating the utility of dialkyl peroxides to accelerate the carbonylations. These findings have potential in elaborating new synthetic protocols for the production of 11C-labeled tracers for positron emission tomography.

  • 254.
    Jin, Mingxing
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Cui, Qiliang
    Mukhtar, Emad
    Ding, Dajun
    Second-harmonic-generation measurements on ZnSe under high pressure2002In: Journal of Physics: Condensed Matter, Vol. 14, p. 11037-11040Article in journal (Refereed)
  • 255.
    Johansson, Anh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Abrahamsson, Malin
    Magnuson, Ann
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Huang, Ping
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Mårtensson, Jerker
    Styring, Stenbjörn
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Hammarström, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Sun, Licheng
    Åkermark, Björn
    Synthesis and Photophysics of One Mononuclear Mn(III) and One Dinuclear Mn(III,III) Complex Covalently Linked to a Ruthenium(II) Tris(bipyridyl) Complex2003In: Inorganic Chemistry, Vol. 42, p. 7502-7511Article in journal (Refereed)
    Abstract [en]

    The preparation of donor (D)-photosensitizer (S) arrays, consisting of a manganese complex as D and a ruthenium tris(bipyridyl) complex as S has been pursued. Two new ruthenium complexes containing coordinating sites for one (2a) and two manganese ions (3a) were prepared in order to provide models for the donor side of photosystem II in green plants. The manganese coordinating site consists of bridging and terminal phenolate as well as terminal pyridyl ligands. The corresponding ruthenium-manganese complexes, a manganese monomer 2b and dimer 3b, were obtained. For the dimer 3b, our data suggest that intramolecular electron transfer from manganese to photogenerated ruthenium(III) is fast, k(ET) > 5 x 10(7) s(-1).

  • 256.
    Johansson, Anh
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Abrahamsson, Malin
    Magnusson, Ann
    Huang, Ping
    Mårtensson, Jerker
    Styring, Stenbjörn
    Hammarström, Leif
    Sun, Licheng
    Åkermark, Björn
    Synthesis and Photophysics of One Mononuclear Mn(III) and One Dinuclear Mn(III,III) Complex Covalently Linked to a Ruthenium(II) Tris(bipyridyl) Complex2003In: Inorganic Chemistry, Vol. 42, p. 7502-7511Article in journal (Refereed)
  • 257.
    Johansson, Erik M .J.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics I.
    Sandell, A.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics I.
    Siegbahn, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics I.
    Rensmo, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics I.
    Mahrov, B.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics I.
    Boschloo, Gerrit
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Figgemeier, E.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Hagfeldt, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Jönsson, S.K.M.
    Fahlman, Mats
    Interfacial Properties of Photovoltaic TiO2/dye/PEDOT-PSS Heterojunctions2005In: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 149, no 2-3, p. 157-167Article in journal (Refereed)
    Abstract [en]

    Systems comprising a dense TiO2 film electrode, a ruthenium polypyridine dye and a PEDOT–PSS(poly(3,4-ethylenedioxythiophene)–poly(4-styrenesulphonate)) film were prepared. The heterojunctions were shown to have photovoltaicproperties, with the dye absorbing the light, the TiO2 acting as an electron conducting material and PEDOT–PSS acting as a hole transport material. A series of dyes was used to investigate their influence on the photocurrent and the photovoltage characteristics of the heterojunction. These results were compared to a photoelectrochemical system in which the PEDOT–PSS was replaced by a liquid electrolyte containing triiodide/iodide redox-couple.

    Photoelectron spectroscopy (PES) was used to monitor the interfacialproperties of the heterojunction and the investigation points out effects of importance when assembling the materials together to a functional unit. Specifically, it was concluded that the interaction with the dye clearly affects the structure ofPEDOT–PSS, both with respect to the surface composition of PSS relative to PEDOT and with respect to the chemical state of the sulphur in the polymers. Moreover, a comparison of the Ru3d and the valence band spectra of the two different interfaces (dye/TiO2 and dye/PEDOT–PSS) indicates that the energy level structure of the dyes compared to the substrate is different for the two surfaces. Thus, in the combined energy level picture under dark conditions, the energy levels in TiO2 relative to the energy levels inPEDOT–PSS depend on the dye.

  • 258.
    Johansson, Mary-Katherine
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Fidder, Henk
    Dick, Daren
    Cook, Ronald M.
    Intramolekular Dimers: A New Strategy to Fluorescence Quenching in Dual-Labeled Oligonucleotide Probes2002In: Journal of American Chemical Society, Vol. 124, p. 6950-6956Article in journal (Refereed)
  • 259. Johansson, Olof
    et al.
    Borgström, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Lomoth, Reiner
    Palmblad, Magnus
    Bergquist, Jonas
    Hammarström, Leif
    Sun, Licheng
    Åkermark, Björn
    Electron Donor-Acceptor Dyads Based on Ruthenium(II) Bipyridine and Terpyridine Complexes Bound to Naphtalenediimide2003In: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 42, p. 2908-2918Article in journal (Refereed)
  • 260.
    Johansson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Photochemistry and Molecular Science, Molecular Biomimetics. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Photochemistry and Molecular Science, Chemical Physics. Avdelningen för molekylär biomimetik.
    Lomoth, Reiner
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Photochemistry and Molecular Science, Molecular Biomimetics. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Photochemistry and Molecular Science, Chemical Physics.
    Rapid electrochemically induced linkage isomerism in a ruthenium(II) polypyridyl complex2005In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, no 12, p. 1578-80Article in journal (Refereed)
  • 261. Johansson, Olof
    et al.
    Wolpher, Henriette
    Borgström, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Hammarström, L.eif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Bergquist, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry, Analytical Chemistry.
    Sun, Licheng
    Åkermark, Björn
    Intramolecular charge separation in a hydrogen bonded tyrosine-ruthenium(II)-naphthalene diimide triad2004In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, no 2, p. 194-195Article in journal (Refereed)
    Abstract [en]

    Long-lived charge-separated states in the ns to [micro sign]s range were observed upon laser flash excitation of a donor-chromophore-acceptor triad based on tris(bipyridine) ruthenium(ii) as photo-sensitizer, naphthalene diimide as acceptor, and a hydrogen bonded phenol as donor.

  • 262. Johansson, Olof
    et al.
    Wolpher, Henriette
    Borgström, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Lomoth, Reiner
    Hammarström, Leif
    Bergquist, Jonas
    Sun, Licheng
    Åkermark, Björn
    Intramolecular Charge Separation in a Hydrogen Bonded Tyrosine-Ruthenium(II)-Naphtalene Diimide Triad2004In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, p. 194-195Article in journal (Refereed)
  • 263.
    Johanssson, Erik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Sandell, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Siegbahn, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Rensmo, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Mahrov, Boriss
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Boschloo, Gerrit
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Figgemeier, E
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Hagfeldt, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Jönsson, Stina
    Fahlman, Mats
    Interfacial properties of photovoltaic TiO2/dye/PEDOT–PSS heterojunctions2005In: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 149, no 2-3, p. 157-167Article in journal (Refereed)
    Abstract [en]

    Systems comprising a dense TiO2 film electrode, a ruthenium polypyridine dye and a PEDOT-PSS (poly(3,4-ethylenedioxythiophene)-poly(4-styrenesulphonate)) film were prepared. The heterojunctions were shown to have photovoltaic properties, with the dye absorbing the light, the TiO2 acting as an electron conducting material and PEDOT-PSS acting as a hole transport material. A series of dyes was used to investigate their influence on the photocurrent and the photovoltage characteristics of the heterojunction. These results were compared to a photoelectrochemical system in which the PEDOT-PSS was replaced by a liquid electrolyte containing triiodide/iodide redox-couple.Photoelectron spectroscopy (PES) was used to monitor the interfacial properties of the heterojunction and the investigation points out effects of importance when assembling the materials together to a functional unit. Specifically, it was concluded that the interaction with the dye clearly affects the structure of PEDOT-PSS, both with respect to the surface composition of PSS relative to PEDOT and with respect to the chemical state of the sulphur in the polymers. Moreover, a comparison of the Ru3d and the valence band spectra of the two different interfaces (dye/TiO2 and dye/PEDOT-PSS) indicates that the energy level structure of the dyes compared to the substrate is different for the two surfaces. Thus, in the combined energy level picture under dark conditions, the energy levels in TiO2 relative to the energy levels in PEDOT-PSS depend on the dye.

  • 264.
    Johnsson, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry. Department of Physical and Analytical Chemistry, Physical Chemistry I.
    Bergstrand, N.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry. Department of Physical and Analytical Chemistry, Physical Chemistry I.
    Phase behavior of DOPE/TritonX100 (reduced) in dilute aqueous solution: aggregate structure and pH-dependence2004In: Colloids and Surfaces B-Biointerfaces, Vol. 34, no 2, p. 69-76Article in journal (Other scientific)
  • 265.
    Johnsson, M
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Edwards, K
    Interactions between nonionic surfactants and sterically stabilized phophatidyl choline liposomes2000In: LANGMUIR, ISSN 0743-7463, Vol. 16, no 23, p. 8632-8642Article in journal (Refereed)
    Abstract [en]

    The interactions between sterically stabilized (EPC/PEG-lipid) liposomes and the nonionic surfactants octyl glucoside (OG) and octa(ethylene glycol) n-dodecyl monoether (C12E8) have been studied. Cryogenic transmission electron microscopy revealed that po

  • 266.
    Johnsson, M
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Edwards, K
    Phase behavior and aggregate structure in mixtures of dioleoylphosphatidylethanolamine and poly(ethylene glycol)-lipids2001In: BIOPHYSICAL JOURNAL, ISSN 0006-3495, Vol. 80, no 1, p. 313-323Article in journal (Refereed)
    Abstract [en]

    Cryo-transmission electron microscopy has been used to investigate the phase behavior and aggregate structure in dilute aqueous mixtures of dioleoylphosphatidylethanolamine (DOPE) and poly(ethylene glycol)-phospholipids (PEG-lipids). It is shown that PEG-

  • 267.
    Johnsson, M
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Hansson, P
    Edwards, K
    Spherical micelles and other self-assembled structures in dilute aqueous mixtures of poly(ethylene glycol) lipids2001In: JOURNAL OF PHYSICAL CHEMISTRY B, ISSN 1089-5647, Vol. 105, no 35, p. 8420-8430Article in journal (Refereed)
    Abstract [en]

    In this work we report on the characteristics of dilute mixtures of poly(ethylene glycol) derivatized lipids (PEG lipids) in aqueous solution. We show that for PEG lipids with PEG of molecular weight 750, 2000, and 5000 covalently coupled to DSPE (distear

  • 268.
    Johnsson, Markus
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Sterically stabilised liposomes and related lipid aggregates: Fundamental studies on aggragate structure and stability2001Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Various aspects of and approaches towards the steric stabilisation of liposomes have been investigated, mainly by use of fluorescence techniques and cryo-transmission electron microscopy (cryo-TEM). It is shown that PEG(2000)-lipids can be incorporated in the liposome membrane up to a critical concentration of 8-10 mol% without any observable structural perturbations. Above 10 mol%, a breakdown of the liposome structure into flat lamellar discs was observed. The sterically stabilised liposomes displayed similar, or even reduced, membrane permeability as compared with conventional liposomes. The presence of PEG-lipids in the EPC membrane was shown to affect the liposome-to-micelle transition in mixtures containing OG. Little or no effects of the PEG-lipids were found on the transition in mixtures containing C12E8.

    The interactions between a number of PEO-PPO-PEO triblock copolymers and PC or PC/Chol liposomes have been investigated. It is shown that these polymers adsorb rapidly onto the liposome surface and induce a substantial increase in membrane permeability as well as structural perturbations. No evidence of an effective steric stabilisation due to the presence of the polymers at the membrane surface was found. This was shown, by the use of a QCM-technique, to be a consequence of the weak interaction between the polymers and the lipid membrane.

    Dispersions of reversed lipid phases in mixtures of DOPE and PEG-lipids were characterised using cryo-TEM. Dispersions displaying reasonable colloidal stability were obtained and particles exhibiting a periodic dense inner structure were observed.

    PEG-lipid micelles were characterised mainly using light scattering techniques. Micelle aggregation numbers and hydrodynamic radii were determined as a function of temperature. It is shown that the inter-micellar interactions are dominated by the steric repulsion.

    PEG-lipid stabilised liposomes loaded with boronated drugs intended for BNCT have been characterised. The drugs were efficiently encapsulated into the liposomes, resulting in a drug precipitation in the water core of the liposomes.

  • 269.
    Johnsson, Markus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Bergstrand, Nill
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Edwards, Katarina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Optimization of drug loading procedures and characterization of liposomal formulations of two novel agents intended for Boron Neutron Capture Therapy (BNCT)1999In: Journal of liposome research, ISSN 0898-2104, E-ISSN 1532-2394, Vol. 9, no 1, p. 53-79Article in journal (Refereed)
    Abstract [en]

    The characterization of two liposomal formulations of boronated DNA-interacting agents has been performed. It is shown that the two boronated drugs, WSA-Water Soluble Acridine and WSP-Water Soluble Phenantridine, can be encapsulated within unilamellar sterically stabilized liposomes with high drug-to-lipid ratios (up to 0.50:1 (mol:mol)), using transmembrane pH gradients. The steric stabilization of the liposomes was accomplished by the addition of DSPE-PEG(2000) (PEG-lipid) to DSPC/Cho lipid mixtures and the composition used was DSPC:Cho:DSPE-PEG 55:40:5 (mol%). The loading of the drugs resulted in drug precipitation in the liposomal aqueous core as observed by cryo-transmission electron microscopy (c-TEM). Moreover, it is shown that when pH gradients across the bilayer were used for remote loading of WSP or when ammonium sulfate gradients were used for remote loading of WSA, the formation of small bilayer fragments (discs) was induced. We present compelling evidence that the formation of discs is a consequence of precipitate growth in the liposomal interior. The precipitate growth causes some of the liposomes to rupture resulting in the above mentioned disc-formation and a substantial decrease in trapping efficiency. The in vitro stability of the drug loaded liposomes was excellent, both in buffer and in 25% human serum. For most of the formulations, the release of the drugs was below or around 10% after 24 hours at 37 degrees C. Furthermore, the influence of initial internal pH and internal buffering capacity on release properties of WSA and WSP were investigated. It is shown that the release profiles of the drugs can be controlled, to a large extent, by varying the composition of the internal liposomal aqueous phase.

  • 270.
    Johnsson, Markus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Bergstrand, Nill
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Stålgren, Johan
    Edwards, Katarina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Stålgren, Johan J. R.
    Adsorption of a PEO-PPO-PEO triblock copolymer on small unilamellar vesicles: equilibrium and kinetic properties and correlation with membrane permeability2001In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 17, no 13, p. 3902-3911Article in journal (Refereed)
    Abstract [en]

    The adsorption of the triblock copolymer F127, poly(ethylene oxide)−poly(propylene oxide)−poly(ethylene oxide), EO98PO67EO98, onto immobilized small unilamellar vesicles (SUVs) of egg phosphatidylcholine (EPC) has been studied by means of a quartz crystal microbalance (QCM). With this technique we first show that SUVs of EPC adsorb on gold to form a monolayer of vesicles. This supported monolayer of vesicles was then used to follow the adsorption of the F127 polymer onto the lipid membrane surface. The adsorption of F127 was found to be a rapid process, and the measured polymer binding isotherm was fitted to a Freundlich type of isotherm. The maximum, or plateau, adsorbed amount was determined to be of a magnitude similar to that found for adsorption of F127 on hydrophobic surfaces. Furthermore, the desorption of the triblock copolymers from the membrane surface was followed after rinsing the SUV monolayer with pure buffer. It was found that the desorption process displayed essentially the same rapid kinetics as the adsorption process, indicating a weak interaction between the polymers and the lipid membrane. The determined polymer binding isotherm was used to correlate the adsorbed amount of polymer with the polymer-induced leakage of carboxy fluorescein (CF) from the SUVs. It was found that the membrane permeability was increased severalfold already at low surface coverage and that the maximum magnitude of the CF release rate was obtained at, or close to, F127 concentrations giving rise to the maximum adsorbed amount of polymer. In addition, the increased membrane permeability induced by the triblock copolymers was compared with the effect of adding a conventional ethylene oxide (EO) surfactant, Triton X-100, to the SUVs. The result emphasizes the dramatic effect of F127 on the bilayer permeability.

  • 271.
    Johnsson, Markus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Edwards, Katarina
    Liposomes, Disks, and Spherical Micelles: Aggregata Structure in Mixtures of Gel Phase Phosphatidylcholines and Poly(Ethylene Glycol)-Phospholipids2003In: Biophysical Journal, Vol. 85, p. 3839-3847Article in journal (Refereed)
  • 272.
    Johnsson, Markus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Silvander, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Karlsson, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Edwards, Katarina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Effect of PEO-PPO-PEO Triblock Copolymers on Structure and Stability of Phosphatidylcholine Liposomes1999In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 15, no 19, p. 6314-6325Article in journal (Refereed)
    Abstract [en]

    The interactions of five poly(oxyethylene)-poly(oxypropylene)-poly(oxyethylene) (PEO-PPO-PEO), Pluronic, copolymers and phosphatidylcholine liposomes of varying composition have been studied. Structural studies were performed by means of cryo-transmission electron microscopy (c-TEM) and reveal that inclusion of low amounts (similar to 2 mol %) of Pluronics gives rise to significant morphological changes of the liposome preparations. Pluronics with large poly(oxyethylene) (PEO) blocks, such as F127, F108, and F87, induce the formation of bilayer disks, whereas those with comparably short PEO blocks, P105 and P85, tend to to promote a reduction in the liposome size. Inclusion of cholesterol in the liposomal preparations reduces the incorporation of copolymers in the lipid bilayer and thus reduces, and in some cases even abolishes, the morphological changes observed in the absence of cholesterol. The effect of the copolymers on liposome permeability was also investigated. All investigated copolymers were found to increase the leakage of carboxyfluorescein from preformed liposomes. This was true also in the case of cholesterol-containing Liposomes despite the fact that no change in the liposome structure could be observed by means of c-TEM. The magnitude of the induced leakage was found to correlate well with the hydrophobicity, as measured by the cmc, of the respective Pluronic. By raising the temperature or decreasing the solvency of the copolymer in the solution, the effect of the copolymer on liposome leakage was found to increase significantly.

  • 273.
    Johnsson, Markus
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Wagenaar, Anno
    Stuart, Marc C.A.
    Engberts, Jan B.F.N.
    Sugar-Based Gemini Surfactants with pH-Dependent Aggregation Behavior: Vesicle-to-Micelle Transition, Critical Micelle Concentration, and Vesicle Surface Charge Reversal2003In: Langmuir, Vol. 19, p. 4609-4618Article in journal (Refereed)
  • 274.
    Kadi, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Davidsson, J.
    The photodissociation dynamics of dibromobenzenes and tribromobenzene in the gas phase studied with femtosecond pump-probe spectroscopy2003In: Chem. Phys. Lett., Vol. 378, p. 172-177Article in journal (Refereed)
  • 275.
    Kadi, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Davidsson, J.
    Tarnovsky, A. N.
    Rasmusson, M.
    Åkesson, E.
    Photodissociation of aryl halides in the gas phase studied with femtosecond pump-probe spectroscopy2001In: Chem. Phys. Lett., Vol. 350, p. 93-98Article in journal (Refereed)
  • 276.
    Kadi, M
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Davidsson, J
    Tarnovsky, AN
    Rasmusson, M
    Åkesson, E
    Photodissociation of aryl halides in the gas phase studied with femtosecond pump-probe spectroscopy2001In: Chemical Physics Letters, Vol. 350, p. 93-98Article in journal (Refereed)
  • 277.
    Kadi, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Dvinskikh, S. V.
    Furó, I.
    Almgren, M.
    Molecular Mechanism of Lateral Diffusion of Fluorosurfactants. A 19F NMR Study2002In: Langmuir, Vol. 18, no 12, p. 5015-5018Article in journal (Refereed)
  • 278.
    Kadi, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Dvinskikh, S.V.
    Furó, I.
    Almgren, M.
    Molecular Mechanism of Lateral Diffusion of Fluorosurfactants. A 19F NMR Study2002In: Langmuir, Vol. 18, p. 5015-5018Article in journal (Refereed)
  • 279.
    Kadi, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Hansson, P.
    Almgren, M.
    Determination of Isoterms for Binding of Surfactants to Vesicles Using a Surfactant Selective ElectrodeArticle in journal (Refereed)
  • 280.
    Kadi, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry. Department of Physical and Analytical Chemistry, Physical Chemistry I.
    Hansson, P
    Medicinska vetenskapsområdet, Faculty of Pharmacy, Department of Pharmacy. Department of Physical and Analytical Chemistry, Physical Chemistry I.
    Almgren, M.
    Determination of Isotherms for Binding of Surfactants to Vesicles Using a Surfactant-Selective Electrode2004In: Journal of Physical Chemistry B, Vol. 108, no 22, p. 7344-7351Article in journal (Refereed)
  • 281.
    Kadi, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Hansson, P.
    Almgren, M.
    Bergström, M.
    Garamus, V. M.
    Mixed Micelles of Fluorocarbon and Hydrocarbon Surfactants. A Small Angle Neutron Scattering StudyManuscript (Other academic)
  • 282.
    Kadi, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry. Department of Physical and Analytical Chemistry, Physical Chemistry I.
    Hansson, P
    Medicinska vetenskapsområdet, Faculty of Pharmacy, Department of Pharmacy. Department of Physical and Analytical Chemistry, Physical Chemistry I.
    Almgren, M.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry. Department of Physical and Analytical Chemistry, Physical Chemistry I.
    Bergström, M.
    Garamus, V. M.
    Mixed micelles of fluorocarbon and hydrocarbon surfactants. A small angle neutron scattering study2004In: Langmuir, Vol. 20, no 10, p. 3933-3939Article in journal (Refereed)
  • 283.
    Kadi, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Hansson, P.
    Almgren, M.
    Furó, I.
    Demixing of Fluorinated and Hydrogenated Surfactants into Distinct Aggregates and into Distinct Regions Within Aggregates. A Combined NMR, Fluorescence Quenching and Cryo-TEM Study2002In: Langmuir, Vol. 18, no 24, p. 9243-9249Article in journal (Refereed)
  • 284.
    Kadi, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Ivarsson, E.
    Davidsson, J.
    The photodissociation dynamics of o-, m- and p-bromotoluene in the gas phase studied with femtosecond pump-probe spectroscopyIn: Chem. Phys. Lett.Article in journal (Refereed)
  • 285.
    Kadi, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry. Department of Physical and Analytical Chemistry, Physical Chemistry I.
    Ivarsson, E.
    Davidsson, J.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry. Department of Physical and Analytical Chemistry, Physical Chemistry I.
    The photodissociation dynamics of o-, m- and p-bromotoluene in the gas phase studied with femtosecond pump-probe spectroscopy2004In: Chemical Physics Letters, Vol. 384, no 1-3, p. 35-39Article in journal (Refereed)
  • 286.
    Kadi, Malin
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Ultrafast Photo-induced Reaction Dynamics of Small Molecules2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The main focus of this thesis is the investigation of the dissociation dynamics of aryl halides using femtosecond pump-probe spectroscopy. In the monohalogenated aryl halides, iodo-, bromo- and chlorobenzene, the rate of dissociation following excitation at 266 nm in the gas phase increased with increasing mass of the halogen atom. This process was assigned to predissociation of the initially excited singlet (π, π*) state via a repulsive triplet (n, σ*) state due to spin-orbit interaction. In addition to the predissociative mechanism, a direct dissociation channel was observed in iodobenzene. The rate of the predissociation in bromobenzene was found to be faster in the condensed phase than in the gas phase, which can be explained by solvent-induced symmetry perturbations. Ab initio calculations of the potential energy surfaces of the ground state and several low lying excited states in bromobenzene have been performed in order to verify the suggested mechanism. Substituting one of the hydrogen atoms in bromobenzene affected the predissociation rate significantly. In o-, m- and p-dibromobenzene the predissociation rate increased with decreasing distance between the bromine atoms in accordance with an increased spin-orbit interaction introduced by the bromine substituent. The fastest predissociation rate was observed in 1,3,5-tribromobenzene. With chlorine and fluorine substitution, inductive and conjugative effects were found to be of importance. In the o- and m-isomers of the dihalogenated aryl halides, an additional faster dissociation channel was observed. Guided by ab initio calculations of the potential energy surfaces in the dibromobenzene isomers, we ascribed the fast dissociation pathway to predissociation of an initially excited triplet state. Upon methyl group substitution in bromobenzene, the decreased lifetime of the initially excited state was attributed to an incresaed density of coupled states.

    Another system which has been studied in the condensed phase is diiodomethane. Using Car-Parrinello molecular dynamics simulations we observed a prompt dissociation and subsequent recombination to the isomer, iso-diiodomethane, in acetonitrile solution.

    Vibrational wavepacket dynamics in the C (1Σ+) state of NaK were studied using a direct ionization probing scheme. A simple analytical expression for the pump-probe signal was developed in order to see what factors that govern direct ionization of the vibrational wavepacket. Our experimental data was consistent with a photoionization transition dipole moment that varies with internuclear distance.

    List of papers
    1. Photodissociation of aryl halides in the gas phase studied with femtosecond pump-probe spectroscopy
    Open this publication in new window or tab >>Photodissociation of aryl halides in the gas phase studied with femtosecond pump-probe spectroscopy
    Show others...
    2001 In: Chem. Phys. Lett., Vol. 350, p. 93-98Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-90875 (URN)
    Available from: 2003-09-24 Created: 2003-09-24Bibliographically approved
    2. Photodissociation of bromobenzene in solution
    Open this publication in new window or tab >>Photodissociation of bromobenzene in solution
    Show others...
    2003 In: Chem. Phys. Lett., Vol. 367, p. 759-766Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-90876 (URN)
    Available from: 2003-09-24 Created: 2003-09-24Bibliographically approved
    3. The photodissociation dynamics of o-, m- and p-bromotoluene in the gas phase studied with femtosecond pump-probe spectroscopy
    Open this publication in new window or tab >>The photodissociation dynamics of o-, m- and p-bromotoluene in the gas phase studied with femtosecond pump-probe spectroscopy
    In: Chem. Phys. Lett.Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-90877 (URN)
    Available from: 2003-09-24 Created: 2003-09-24Bibliographically approved
    4. The photodissociation dynamics of dibromobenzenes and tribromobenzene in the gas phase studied with femtosecond pump-probe spectroscopy
    Open this publication in new window or tab >>The photodissociation dynamics of dibromobenzenes and tribromobenzene in the gas phase studied with femtosecond pump-probe spectroscopy
    2003 In: Chem. Phys. Lett., Vol. 378, p. 172-177Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-90878 (URN)
    Available from: 2003-09-24 Created: 2003-09-24Bibliographically approved
    5. The photodissociation of bromobenzene, dibromobenzene and 1,3,5-tribromobenzene
    Open this publication in new window or tab >>The photodissociation of bromobenzene, dibromobenzene and 1,3,5-tribromobenzene
    Show others...
    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:uu:diva-90879 (URN)
    Available from: 2003-09-24 Created: 2003-09-24 Last updated: 2010-01-13Bibliographically approved
    6. Photodissociation of diiodomethane and recombination into iso-diiodomethane in acetonitrile solution studied with ab initio molecular dynamics simulations
    Open this publication in new window or tab >>Photodissociation of diiodomethane and recombination into iso-diiodomethane in acetonitrile solution studied with ab initio molecular dynamics simulations
    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:uu:diva-90880 (URN)
    Available from: 2003-09-24 Created: 2003-09-24 Last updated: 2010-01-13Bibliographically approved
    7. Photoionization of molecular wavepackets - the NaK (C1Σ+) case
    Open this publication in new window or tab >>Photoionization of molecular wavepackets - the NaK (C1Σ+) case
    2002 In: Chem. Phys. Lett., Vol. 352, p. 106-112Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-90881 (URN)
    Available from: 2003-09-24 Created: 2003-09-24Bibliographically approved
  • 287.
    Kadi, Malin
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Davidsson, Jan
    The photodissociation dynamics of dibromobenzenes and tribromobenzene in the gas phase studied with femtosecond pump-probe spectroscopy2003In: Chemical Physics Letters, Vol. 378, p. 172-177Article in journal (Refereed)
  • 288.
    Kadi, Mari
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Bilayers with Surfactant-induced Pores and Demixing in Micelles: Studies of Segregation in Amphiphile Systems2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The focus of this thesis has been on the effects of segregation in mixtures of amphiphilic molecules. Two different systems were investigated: fluorocarbon-hydrocarbon surfactant mixtures and lipid-surfactant mixtures.

    In fluorocarbon-hydrocarbon surfactant mixtures the repulsive interactions between the chains can lead to a demixing into different types of coexisting micelles, fluorocarbon rich and hydrocarbon rich. From NMR self-diffusion measurements such a demixing was found to occur in the mixture of the partially fluorinated surfactant HFDePC and C16TAC. We furthermore suggested a demixing also within the micelles to explain 19F-NMR line width data and results from neutron scattering.

    In lipid-surfactant mixtures, a segregation of the molecules may instead be caused by a difference in the preferred curvature of the lipid and the surfactant residing within the same aggregate. Using a surfactant selective electrode, binding isoterms of four different cationic surfactants (C12TAC, C14TAC, C16TAC and HFDePC) to preformed lipid (GMO) vesicles were determined. Perforated vesicles were observed by cryo-TEM in the mixture with C16TAC. To explain the results from the binding isoterms, the formation of pores in the bilayer was regarded as a cooperative process, similar to micelle formation. The surfactant accumulates at the edges of the pores, and increasing the surfactant concentration results in an increased number of pores with a constant surfactant/lipid ratio at the edges.

    The lipid-surfactant mixtures were also studied at the solid/solution interface using AFM. An adsorbed mesh structure, a counterpart to the bulk perforated lamellar phase, was observed for the first time.

    List of papers
    1. Molecular Mechanism of Lateral Diffusion of Fluorosurfactants. A 19F NMR Study
    Open this publication in new window or tab >>Molecular Mechanism of Lateral Diffusion of Fluorosurfactants. A 19F NMR Study
    2002 In: Langmuir, Vol. 18, no 12, p. 5015-5018Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-90803 (URN)
    Available from: 2003-09-12 Created: 2003-09-12Bibliographically approved
    2. Demixing of Fluorinated and Hydrogenated Surfactants into Distinct Aggregates and into Distinct Regions Within Aggregates. A Combined NMR, Fluorescence Quenching and Cryo-TEM Study
    Open this publication in new window or tab >>Demixing of Fluorinated and Hydrogenated Surfactants into Distinct Aggregates and into Distinct Regions Within Aggregates. A Combined NMR, Fluorescence Quenching and Cryo-TEM Study
    2002 In: Langmuir, Vol. 18, no 24, p. 9243-9249Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-90804 (URN)
    Available from: 2003-09-12 Created: 2003-09-12Bibliographically approved
    3. Mixed Micelles of Fluorocarbon and Hydrocarbon Surfactants. A Small Angle Neutron Scattering Study
    Open this publication in new window or tab >>Mixed Micelles of Fluorocarbon and Hydrocarbon Surfactants. A Small Angle Neutron Scattering Study
    Show others...
    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:uu:diva-90805 (URN)
    Available from: 2003-09-12 Created: 2003-09-12 Last updated: 2010-01-13Bibliographically approved
    4. Determination of Isoterms for Binding of Surfactants to Vesicles Using a Surfactant Selective Electrode
    Open this publication in new window or tab >>Determination of Isoterms for Binding of Surfactants to Vesicles Using a Surfactant Selective Electrode
    Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-90806 (URN)
    Available from: 2003-09-12 Created: 2003-09-12Bibliographically approved
    5. Direct Visualization of Mesh Phases at Solid/Solution Interfaces by AFM
    Open this publication in new window or tab >>Direct Visualization of Mesh Phases at Solid/Solution Interfaces by AFM
    Show others...
    Article in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-90807 (URN)
    Available from: 2003-09-12 Created: 2003-09-12Bibliographically approved
  • 289.
    Kadi, Mari
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical Chemistry.
    Hansson, Per
    Almgren, Mats
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical and Analytical Chemistry.
    Furó, I
    Demixing of Flourinated and Hydrogenated Surfactants into Distinct Aggregates and into Distinct Regions within Aggregates. A Combined NMR, Flourescence Quenching, and Cryo-TEM Study2002In: Langmuir, Vol. 18, p. 9243-9249Article in journal (Refereed)
  • 290.
    Karlsson, P. G.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics I.
    Bolik, S.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Richter, J. H.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Mahrov, B.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Johansson, E. M. J.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Blomquist, J.
    Uvdal, P.
    Rensmo, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Siegbahn, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics I.
    Sandell, A.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Interfacial Properties of the Nanostructured Dye-Sensitized Solid Heterojunction TiO2/RuL2(NCS)2/CuI2004In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 120, no 23, p. 11224-11232Article in journal (Refereed)
    Abstract [en]

    The interfaces of the nanostructured dye-sensitized solid heterojunction TiO2/Ru–dye/CuIhave been studied using photoelectron spectroscopy of core and valence levels, x-ray absorption spectroscopy and atomic force microscopy. A nanostructured anatase TiO2 film sensitized with RuL2(NCS)2 [cis-bis(4,4-dicarboxy-2,2-bipyridine)-bis(isothio-cyanato)-ruthenium(II)] was prepared in a controlled way using a novel combined in-situ and ex-situ(Ar atmosphere) method. Onto this film CuI was deposited in-situ. The formation of the dye–CuI interface and the changes brought upon the dye–TiO2 interface could be monitored in a stepwise fashion. A direct interaction between the dye NCS groups and the CuI is evident in the core level photoelectron spectra. Concerning the energy matching of the valence electronic levels, the photoelectron spectra indicate that the dye HOMO overlaps in energy with the Cu 3d–I 5p hydrid states. The CuI grow in the form of particles, which at the initial stages displace the dye molecules causing dye–TiO2 bond breaking. Consequently, the very efficient charge injection channel provided by the dye–TiO2carboxylic bonding is directly affected for a substantial part of the dye molecules. This may be of importance for the functional properties of such a heterojunction

  • 291.
    Karlsson, P. G.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Bolik, S.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Richter, J. H.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Mahrov, B.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical Chemistry.
    Johansson, E. M .J.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics I.
    Blomquist, J.
    Uvdal, P.