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Lüder, Johann
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Publications (10 of 15) Show all publications
Totani, R., Grazioli, C., Zhang, T., Bidermane, I., Lüder, J., de Simone, M., . . . Puglia, C. (2017). Electronic structure investigation of biphenylene films. Journal of Chemical Physics, 146(5), Article ID 054705.
Open this publication in new window or tab >>Electronic structure investigation of biphenylene films
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2017 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 146, no 5, article id 054705Article in journal (Refereed) Published
Abstract [en]

Photoelectron Spectroscopy (PS) and Near-Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy have been used to investigate the occupied and empty density of states of biphenylene films of different thicknesses, deposited onto a Cu(111) crystal. The obtained results have been compared to previous gas phase spectra and single molecule Density Functional Theory (DFT) calculations to get insights into the possible modification of the molecular electronic structure in the film induced by the adsorption on a surface. Furthermore, NEXAFS measurements allowed characterizing the variation of the molecular arrangement with the film thickness and helped to clarify the substrate-molecule interaction. Published by AIP Publishing.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2017
National Category
Chemical Sciences Physical Sciences
Identifiers
urn:nbn:se:uu:diva-320469 (URN)10.1063/1.4975104 (DOI)000394576600053 ()28178795 (PubMedID)
Available from: 2017-04-26 Created: 2017-04-26 Last updated: 2017-04-26Bibliographically approved
Lüder, J., Schött, J., Brena, B., Haverkort, M. W., Thunström, P., Eriksson, O., . . . Kvashnin, Y. (2017). Theory of L-edge spectroscopy of strongly correlated systems. Physical Review B, 96(24), Article ID 245131.
Open this publication in new window or tab >>Theory of L-edge spectroscopy of strongly correlated systems
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2017 (English)In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 96, no 24, article id 245131Article in journal (Refereed) Published
Abstract [en]

X-ray absorption spectroscopy measured at the L edge of transition metals (TMs) is a powerful element-selective tool providing direct information about the correlation effects in the 3d states. The theoretical modeling of the 2p→3d excitation processes remains to be challenging for contemporary ab initio electronic structure techniques, due to strong core-hole and multiplet effects influencing the spectra. In this work, we present a realization of the method combining the density-functional theory with multiplet ligand field theory, proposed in Haverkort et al. [Phys. Rev. B 85, 165113 (2012)]. In this approach, a single-impurity Anderson model (SIAM) is constructed, with almost all parameters obtained from first principles, and then solved to obtain the spectra. In our implementation, we adopt the language of the dynamical mean-field theory and utilize the local density of states and the hybridization function, projected onto TM 3d states, in order to construct the SIAM. The developed computational scheme is applied to calculate the L-edge spectra for several TM monoxides. A very good agreement between the theory and experiment is found for all studied systems. The effect of core-hole relaxation, hybridization discretization, possible extensions of the method as well as its limitations are discussed.

National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:uu:diva-339767 (URN)10.1103/PhysRevB.96.245131 (DOI)000418573600012 ()
Funder
Knut and Alice Wallenberg Foundation, 2013.0020; 2012.0031Carl Tryggers foundation
Available from: 2018-02-02 Created: 2018-02-02 Last updated: 2018-10-10Bibliographically approved
Lüder, J. (2016). Complex Excitations in Advanced Functional Materials. (Doctoral dissertation). Uppsala: Acta Universitatis Upsaliensis
Open this publication in new window or tab >>Complex Excitations in Advanced Functional Materials
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Understanding the fundamental electronic properties of materials is a key step to develop innovations in many fields of technology. For example, this has allowed to design molecular based devices like organic field effect transistors, organic solar cells and molecular switches.

In this thesis, the properties of advanced functional materials, in particular metal-organic molecules and molecular building blocks of 2D materials, are investigated by means of Density Functional Theory (DFT), the GW approximation (GWA) and the Bethe-Salpeter equation (BSE), also in conjunction with experimental studies. The main focus is on calculations aiming to understand spectroscopic results.

In detail, the molecular architectures of lutetium-bis-phthalocyanine (LuPc2) on clean and hydrogenated vicinal Si(100)2×1, and of the biphenylene molecule on Cu(111) were analysed by means of X-ray Photoelectron spectroscopy (XPS) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy; DFT calculations were performed to obtain insights into the atomic and electronic structures. Furthermore, detailed information about the electronic states of the gas phase iron phthalocyanine (FePc) and of the gas phase biphenylene molecule were obtained through XPS and NEXAFS spectroscopy. I have studied by means of DFT, multiplet and GWA calculations the electronic correlation effects in these systems. Also the optical, electronic and excitonic properties of a hypothetical 2D material based on the biphenylene molecule were investigated by GWA and BSE calculations. Monolayers of metal-free phthalocyanine (H2Pc) on Au(111) and of FePc on Au(111) and Cu(100)c(2×2)-2N/Cu(111) with and without pyridine modifier were studied by XPS and final state calculations. A multiplet approach to compute L-edges employing the hybridizations function, known from dynamical mean field theory, was proposed and applied to transition metal oxides.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2016. p. 90
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1365
Keywords
X-ray Absorption Spectroscopy, Photoelectron Spectroscopy, Adsorption, Phthalocyanines, Biphenylene, Excitons, Functional Materials
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:uu:diva-282151 (URN)978-91-554-9543-5 (ISBN)
Public defence
2016-05-13, Å80101, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, 09:15 (English)
Opponent
Supervisors
Available from: 2016-04-22 Created: 2016-04-03 Last updated: 2016-04-29
Brumboiu, I. E., Haldar, S., Luder, J., Eriksson, O., Herper, H. C., Brena, B. & Sanyal, B. (2016). Influence of Electron Correlation on the Electronic Structure and Magnetism of Transition-Metal Phthalocyanines. Journal of Chemical Theory and Computation, 12(4), 1772-1785
Open this publication in new window or tab >>Influence of Electron Correlation on the Electronic Structure and Magnetism of Transition-Metal Phthalocyanines
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2016 (English)In: Journal of Chemical Theory and Computation, Vol. 12, no 4, p. 1772-1785Article in journal (Refereed) Published
Abstract [en]

There exists an extensive literature on the electronic structure of transition-metal phthalocyanines (TMPcs), either as single molecules or adsorbed on surfaces, where explicit intra-atomic Coulomb interactions of the strongly correlated orbitals are included in the form of a Hubbard U term. The choice of U is, to a large extent, based solely on previous values reported in the literature for similar systems. Here, we provide a systematic analysis of the influence of electron correlation on the electronic structure and magnetism of several TMPcs (MnPc, FePc, CoPc, NiPc, and CuPc). By comparing calculated results to valence-band photoelectron spectroscopy measurements, and by determining the Hubbard term from linear response, we show that the choice of U is not as straightforward and can be different for each different TMPc. This, in turn, highlights the importance of individually estimating the value of U for each system before performing any further analysis and shows how this value can influence the final results.

National Category
Physical Sciences Materials Chemistry Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-281097 (URN)10.1021/acs.jctc.6b00091 (DOI)000374196400034 ()26925803 (PubMedID)
Funder
Swedish Research CouncilKnut and Alice Wallenberg Foundation
Available from: 2016-03-17 Created: 2016-03-17 Last updated: 2017-01-25Bibliographically approved
Lüder, J., Puglia, C., Ottosson, H., Eriksson, O., Sanyal, B. & Brena, B. (2016). Many-body effects and excitonic features in 2D biphenylene carbon. Journal of Chemical Physics, 144(2), Article ID 024702.
Open this publication in new window or tab >>Many-body effects and excitonic features in 2D biphenylene carbon
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2016 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 144, no 2, article id 024702Article in journal (Refereed) Published
Abstract [en]

The remarkable excitonic effects in low dimensional materials in connection to large binding energies of excitons are of great importance for research and technological applications such as in solar energy and quantum information processing as well as for fundamental investigations. In this study, the unique electronic and excitonic properties of the two dimensional carbon network biphenylene carbon were investigated with GW approach and the Bethe-Salpeter equation accounting for electron correlation effects and electron-hole interactions, respectively. Biphenylene carbon exhibits characteristic features including bright and dark excitons populating the optical gap of 0.52 eV and exciton binding energies of 530 meV as well as a technologically relevant intrinsic band gap of 1.05 eV. Biphenylene carbon's excitonic features, possibly tuned, suggest possible applications in the field of solar energy and quantum information technology in the future.

National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:uu:diva-278016 (URN)10.1063/1.4939273 (DOI)000368618400036 ()26772582 (PubMedID)
Funder
Knut and Alice Wallenberg Foundation
Available from: 2016-02-23 Created: 2016-02-23 Last updated: 2017-11-30Bibliographically approved
Bidermane, I., Lüder, J., Ahmadi, S., Grazioli, C., Bouvet, M., Brena, B., . . . Witkowski, N. (2016). When the Grafting of Double Decker Phthalocyanines on Si(100)-2 × 1 Partly Affects the Molecular Electronic Structure. The Journal of Physical Chemistry C, 120(26), 14270-14276
Open this publication in new window or tab >>When the Grafting of Double Decker Phthalocyanines on Si(100)-2 × 1 Partly Affects the Molecular Electronic Structure
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2016 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 120, no 26, p. 14270-14276Article in journal (Refereed) Published
Abstract [en]

A combined X-ray photoelectron spectroscopy (XPS), scanning tunneling microscopy (STM), and density functional theory (DFT) study has been performed to characterize the adsorbate interaction of lutetium biphthalocyanine (LuPc2) molecules on the Si(100)-2 × 1 surface. Large molecule–substrate adsorption energies are computed and are found to compete with the molecule–molecule interactions of the double decker molecules. A particularly good matching between STM images and computed ones confirms the deformation of the molecule upon the absorption process. The comparison between DFT calculations and XP spectra reveals that the electronic distribution in the two plateaus of the biphthalocyanine are not affected in the same manner upon the adsorption onto the silicon surface. This finding can be of particular importance in the implementation of organic molecules in hybrid devices.

Keywords
lutetium bi-phthalocyanine, XPS, STM, XAS, DFT, Si(100)
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:uu:diva-281565 (URN)10.1021/acs.jpcc.6b05552 (DOI)000379457000044 ()
Funder
EU, FP7, Seventh Framework Programme, 321319Knut and Alice Wallenberg Foundation, KAW-2013.0020Swedish Research Council, 2014-3776
Available from: 2016-03-24 Created: 2016-03-24 Last updated: 2017-11-30Bibliographically approved
Bidermane, I., Lüder, J., Totani, R., Grazioli, C., de Simone, M., Coreno, M., . . . Puglia, C. (2015). Characterization of Gas Phase of Iron Phthalocyanine with X-ray Photoelectron and Absorption Spectroscopies. Physica status solidi. B, Basic research, 252(6), 1259-1265
Open this publication in new window or tab >>Characterization of Gas Phase of Iron Phthalocyanine with X-ray Photoelectron and Absorption Spectroscopies
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2015 (English)In: Physica status solidi. B, Basic research, ISSN 0370-1972, E-ISSN 1521-3951, Vol. 252, no 6, p. 1259-1265Article in journal (Refereed) Published
Abstract [en]

Despite the numerous studies dedicated to phthalocyanine molecules adsorbed on surfaces, in monolayer or thin film, very few works have been focused on the characterization of vapors of these molecules. In this article we present the C 1s, N 1s and Fe 2p photoemission results as well as N K-edge X-ray absorption data of iron phthalocyanine (FePc) in gas phase. Presented comparison of X-ray photoelectron spectroscopy and X-ray absorption spectroscopy spectra of FePc films show a great similarity with the gas phase results, confirming the molecular character of thick films. The Fe2p photoemission spectrum of the gas phase FePc, shown for the first time, can be considered as a fingerprint of the Fe(II) ionic state of the central metal of the iron phthalocyanine. The performed multiplet calculations for describing the Fe 2p XP spectrum indicate 3Eg (a1g2eg32g1) state as the most probable ground state for thick film of iron phthalocyanine.

National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:uu:diva-217080 (URN)10.1002/pssb.201451147 (DOI)000355756200010 ()
Funder
Swedish Research CouncilCarl Tryggers foundation
Available from: 2014-01-29 Created: 2014-01-29 Last updated: 2017-12-06Bibliographically approved
Snezhkova, O., Lüder, J., Wiengarten, A., Burema, S. R., Bischoff, F., He, Y., . . . Schnadt, J. (2015). Nature of the bias-dependent symmetry reduction of iron phthalocyanine on Cu(111). Physical Review B. Condensed Matter and Materials Physics, 92(7), Article ID 075428.
Open this publication in new window or tab >>Nature of the bias-dependent symmetry reduction of iron phthalocyanine on Cu(111)
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2015 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 92, no 7, article id 075428Article in journal (Refereed) Published
Abstract [en]

Subtle changes in the geometric and electronic properties of supported molecules, with a potential impact on the functioning of molecular devices, can typically be imaged by scanning probe microscopy, but their exact origin and nature often remain unclear. Here we show explicitly that the symmetry reduction of iron phthalocyanine upon adsorption on Cu(111) can be observed not only in scanning tunneling microscopy, but also in core-level spectroscopy, and that it is related to nonisotropic charge transfer into the two principal molecular axes, but in combination with topographic influences.

National Category
Physical Sciences
Identifiers
urn:nbn:se:uu:diva-262426 (URN)10.1103/PhysRevB.92.075428 (DOI)000359859600005 ()
Funder
Swedish Research Council, 2010-5080 2014-3776EU, European Research Council, 247299
Available from: 2015-09-17 Created: 2015-09-15 Last updated: 2017-12-04Bibliographically approved
Luder, J., de Simone, M., Totani, R., Coreno, M., Grazioli, C., Sanyal, B., . . . Puglia, C. (2015). The electronic characterization of biphenylene-Experimental and theoretical insights from core and valence level spectroscopy. Journal of Chemical Physics, 142(7), Article ID 074305.
Open this publication in new window or tab >>The electronic characterization of biphenylene-Experimental and theoretical insights from core and valence level spectroscopy
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2015 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 142, no 7, article id 074305Article in journal (Refereed) Published
Abstract [en]

In this paper, we provide detailed insights into the electronic structure of the gas phase biphenylene molecule through core and valence spectroscopy. By comparing results of X-ray Photoelectron Spectroscopy (XPS) measurements with Delta SCF core-hole calculations in the framework of Density Functional Theory (DFT), we could decompose the characteristic contributions to the total spectra and assign them to non-equivalent carbon atoms. As a difference with similar molecules like biphenyl and naphthalene, an influence of the localized orbitals on the relative XPS shifts was found. The valence spectrum probed by photoelectron spectroscopy at a photon energy of 50 eV in conjunction with hybrid DFT calculations revealed the effects of the localization on the electronic states. Using the transition potential approach to simulate the X-ray absorption spectroscopy measurements, similar contributions from the non-equivalent carbon atoms were determined from the total spectrum, for which the slightly shifted individual components can explain the observed asymmetric features.

National Category
Other Physics Topics
Identifiers
urn:nbn:se:uu:diva-251526 (URN)10.1063/1.4907723 (DOI)000350547500018 ()25702013 (PubMedID)
Available from: 2015-04-22 Created: 2015-04-20 Last updated: 2017-12-04Bibliographically approved
Luder, J., Sanyal, B., Eriksson, O., Puglia, C. & Brena, B. (2014). Comparison of van der Waals corrected and sparse-matter density functionals for the metal-free phthalocyanine/gold interface. Physical Review B. Condensed Matter and Materials Physics, 89(4), 045416
Open this publication in new window or tab >>Comparison of van der Waals corrected and sparse-matter density functionals for the metal-free phthalocyanine/gold interface
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2014 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 89, no 4, p. 045416-Article in journal (Refereed) Published
Abstract [en]

In this paper, we report a systematic study on the effect of different van der Waals dispersion correction methods in conjunction with Density Functional Theory on the adsorption characteristics of a monolayer of metal-free phthalocyanine on Au(111). The chosen dispersion corrections were DFT-D2, the Tkatchenko-Scheffler method with and without self-consistent screening, and four sparse-matter density functionals. A comparison among different dispersion corrections was performed and the results are related to available experimental scanning tunnel microscopy and x-ray standing-wave measurements for similar molecules on Au(111). We found that the Tkatchenko-Scheffler method as well as a sparse-matter density functional which employs the exchange potential of optB86b and the nonlocal correlation of Dion describe the adsorbed system, e. g., electronic and geometric structure with an adsorption distance of 3.3 angstrom, reasonably well within moderate computational costs.

National Category
Natural Sciences
Identifiers
urn:nbn:se:uu:diva-221933 (URN)10.1103/PhysRevB.89.045416 (DOI)000332225400008 ()
Available from: 2014-04-07 Created: 2014-04-07 Last updated: 2017-12-05Bibliographically approved
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