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Photoelectron Spectroscopy on Atoms, Molecules and Clusters

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Photoelectron Spectroscopy on Atoms, Molecules and Clusters Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 375 Photoelectron Spectroscopy on Atoms, Molecules and Clusters The Geometric and Electronic Structure Studied by Synchrotron Radiation and Lasers TORBJÖRN RANDER ACTA UNIVERSITATIS UPSALIENSIS ISSN 1651-6214 UPPSALA ISBN 978-91-554-7047-0 2007 urn:nbn:se:uu:diva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“Och kallas därför höga bergen hos oss fjäll, av orsak att där oppå inga trän eller örter växa, utan de är glatta och bara såsom fjäll uppå en fisk” – Olof Rudbäck d. ä. ListofPapers This thesis is based on the following papers, which are referred to in the text by their Roman numerals. I Experimental evidence for molecular ultrafast dissociation in O2 clusters T. Rander, M. Lundwall, A. Lindblad, G. Öhrwall, M. Tchaplyguine, S. Svensson, O. Björneholm Eur. Phys. J. D 42, 253-257 (2007) II Suppression of the ultrafast dissociation of bromomethane molecules in clusters T. Rander, A. Lindblad, A. Rosso, H. Bergersen, G. Öhrwall, S. Svensson, O. Björneholm In manuscript III Core-level electron spectroscopy on the sodium dimer Na 2p level T. Rander, J. Schulz, M. Huttula, A. Mäkinen, M. Tchaplyguine, S. Svensson, G. Öhrwall, O. Björneholm, S. Aksela, H. Aksela Phys. Rev. A 75, 032510 (2007) IV The diffusion behavior of O2 doped on large Ar clusters T. Rander, A. Lindblad, M. Lundwall, M. Tchaplyguine, G. Öhrwall, S. Svensson, O. Björneholm Submitted to J. Chem. Phys. V The far from equilibrium structure of argon clusters doped with krypton or xenon A. Lindblad, H. Bergersen, T. Rander, M. Lundwall, G. Öhrwall, M. Tchaplyguine, S. Svensson, O. Björneholm Phys. Chem. Chem. Phys. 8, 1899-1905 (2006) 5 VI The role of molecular polarity in cluster local structure studied by photoelectron spectroscopy A. Rosso, T. Rander, H. Bergersen, A. Lindblad, M. Lundwall, S. Svensson, M. Tchaplyguine, G. Öhrwall, L. J. Sæthre, O. Björneholm Chem. Phys. Lett 435, 79-83 (2007) VII Shakedown in core photoelectron spectra from aligned laser-excited Na atoms J. Schulz, M. Tchaplyguine, T. Rander, O. Björneholm, S. Svensson, R. Sankari, S. Heinäsmäki, H. Aksela, S. Aksela, E. Kukk Phys. Rev. A 72, 10702-1-4 (2005) VIII Characterization of weakly excited final states by shakedown spectroscopy of laser-excited potassium J. Schulz, S. Heinäsmäki, R. Sankari, T. Rander, A. Lindblad, H. Bergersen, G. Öhrwall, S. Svensson, E. Kukk, S. Aksela, H. Aksela Phys. Rev. A 74, 12705-1-6 (2006) Reprints were made with permission from the publishers. 6 The following is a list of papers to which I have contributed, but which are not included in this thesis. Observation of elastic scattering effects on photoelectron angular distributions in free Xe clusters G. Öhrwall, M. Tchaplyguine, M. Gisselbrecht, M. Lundwall, R. Feifel, T. Rander, J. Schulz, R. R. T. Marinho, A. Lindgren, S. L. Sörensen, S. Svensson, O. Björneholm J. Phys. B 36, 3937-49 (2003) Femtosecond Interatomic Coulombic Decay in Free Neon Clusters: Large Lifetime Differences between Surface and Bulk G. Öhrwall, M. Tchaplyguine, M. Lundwall, R. Feifel, H. Bergersen, T. Rander, A. Lindblad, J. Schulz, S. Peredkov, S. Barth, S. Marburger, U. Hergenhahn, S. Svensson, and O. Björneholm Phys. Rev. Lett. 93, 173401 (2004) Final state selection in the 4p photoemission of Rb by combining laser spectroscopy with soft-x-ray photoionization J. Schulz, M. Tchaplyguine, T. Rander, H. Bergersen, A. Lindblad, G. Öhrwall, S. Svensson. S. Heinäsmäki, R. Sankari, S. Osmekhin, S. Aksela, H. Aksela Phys. Rev. A 72, 32718-1-4 (2005) The electronic structure of free water clusters probed by Auger electron spectroscopy G. Öhrwall, R. F. Fink, M. Tchaplyguine, L. Ojamae, M. Lundwall, R. R. T. Marinho, A. N. de Brito, S. L. Sörensen, M. Gisselbrecht, R. Feifel, T. Rander, A. Lindblad, J. Schulz, L. J. Sæthre, N. Mårtensson, S. Svensson, O. Björneholm J. Chem. Phys 123, 54310-1-10 (2005) Ioniclike energy structure of neutral core-excited states in free Kr clusters S. Peredkov, A. Kivimäki, S. L. Sörensen, J. Schulz, N. Mårtensson, G. Öhrwall, M. Lundwall, T. Rander, A. Lindblad, H. Bergersen, S. Svensson, O. Björneholm, M. Tchaplyguine Phys. Rev. A 72, 21201-1-4 (2005) 7 Postcollision interaction in noble gas clusters: observation of differences in surface and bulk line shapes A. Lindblad, R. F. Fink, H. Bergersen, M. Lundwall, T. Rander, R. Feifel, G. Öhrwall, M. Tchaplyguine, U. Hergenhahn, S. Svensson, O. Björneholm J. Chem. Phys. 123, 211101-1-4 (2005) Enhanced surface sensitivity in AES relative to XPS observed in free Ar clusters M. Lundwall, M. Tchaplyguine, G. Öhrwall, A. Lindblad, S. Peredkov, T. Rander, S. Svensson, O. Björneholm Surf. Sci. 594, 12-19 (2005) Photon energy dependent intensity variations observed in Auger spectra of free argon clusters M. Lundwall, A. Lindblad, H. Bergersen, T. Rander, G. Öhrwall, M. Tchaplyguine, S. Peredkov, S. Svensson, O. Björneholm J. Phys. B 39, 3321-33 (2006) Shell-dependent core-level chemical shifts observed in free xenon clusters M. Lundwall, R. F. Fink, M. Tchaplyguine, A. Lindblad, G. Öhrwall, H. Bergersen, S. Peredkov, T. Rander, S. Svensson, O. Björneholm J. Phys. B 39, 5225-35 (2006) Lineshapes in carbon 1s photoelectron spectra of methanol clusters M. Abu-samha, K. K. Børve, L. J. Sæthre, G. Öhrwall, H. Bergersen, T. Rander, O. Björneholm, M. Tchaplyguine Phys. Chem. Chem. Phys 8, 2473-82 (2006) Preferential site occupancy of krypton atoms on free argon-cluster surfaces M. Lundwall, A. Lindblad, H. Bergersen, T. Rander, G. Öhrwall, M. Tchaplyguine, S. Svensson, O. Björneholm J. Chem. Phys 125, 14305-1-7 (2006) Laser excitation combined with 2p photoionization and Auger decay of potassium K. Jänkälä, R. Sankari, J. Schulz, M. Huttula, A. Calo, S. Heinäsmäki, S. Fritsche, T. Rander, S. Svensson, S. Aksela, H. Aksela Phys. Rev. A 73, 22720-1-8 (2006) 8 Magnetron-based source of neutral metal vapors for photoelectron spectroscopy M. Tchaplyguine, S. Peredkov, H. Svensson, J. Schulz, G. Öhrwall, M. Lundwall, T. Rander, A. Lindblad, H. Bergersen, S. Svensson, M. Gisselbrecht, S. L. Sorensen, L. Gridneva, N. Mårtensson, O. Björneholm Rev. Sci. Instrum. 77, 033106 (2006) 5p photoemission from laser-excited cesium atoms J. Schulz, M. Määtä, S. Heinäsmäki, M. Huttula, R. Sankari, E. Kukk, T. Rander, S. Svensson, S. Aksela, H. Aksela Phys. Rev. A 73, 062721 (2006) Self-assembled heterogeneous argon/neon core-shell clusters studied by photoelectron spectroscopy M. Lundwall, W. Pokapanich, H. Bergersen, A. Lindblad, T. Rander, G. Öhrwall, M. Tchaplyguine, S. Barth, U. Hergenhahn, S. Svensson, O. Björneholm J. Chem. Phys. 126, 214706 (2007) Synchrotron radiation study of chloromethane clusters: Effects of polarizability and dipole moment on core level chemical shifts A. Rosso, A. Lindblad, M. Lundwall, T. Rander, S. Svensson, M. Tchaplyguine, G. Öhrwall, O. Björneholm J. Chem. Phys. 127, 024302 (2007) Free nanoscale sodium clusters studied by core-level photoelectron spectroscopy S. Peredkov, G. Öhrwall, J. Schulz, M. Lundwall, T. Rander, A. Lindblad, H. Bergersen, A. Rosso, W. Pokapanich, N. Mårtensson, S. Svensson, S. L. Sorensen, O. Björneholm Phys. Rev. B 75, 235407 (2007) Direct observation of the non-supported metal nanoparticle electron density of states by X-ray photoelectron spectroscopy M. Tchaplyguine, S. Peredkov, A. Rosso, J. Schulz, G. Öhrwall, M. Lundwall, T. Rander, A. Lindblad, H. Bergersen, W. Pokapanich, S. Svensson, S. L. Sorensen, N. Mårtensson, O. Björneholm Eur. Phys. J. D 45, 295 (2007) 9 Localized versus delocalized excitations just above the 3d threshold in krypton clusters studied by Auger electron spectroscopy M. Tchaplyguine, A. Kivimäki, S. Peredkov, S. L. Sorensen, G. Öhrwall, J. Schulz, M. Lundwall, T. Rander, A. Lindblad, A. Rosso, S. Svensson, N. Mårtensson, O. Björneholm J. Chem. Phys. 127, 124314 (2007) 10 Contents List of Papers . 3 Comments on my own participation . 12 1 Populärvetenskaplig sammanfattning . 15 1.1 De olika experimenten . 15 1.2 Experimentella metoder . 17 1.2.1 Elektromagnetisk strålning . 17 1.2.2 Elektronspektroskopi . 17 1.3 Beräkningar . 19 1.4 Resultat . 19 2 Introduction . 21 3 Fundamental concepts . 23 3.1 The electronic structure of matter . 23 3.1.1 Atoms . 23 3.1.2 Molecules . 25 3.1.3 Clusters and solids . 27 3.2 The geometric structure of matter . 28 3.3 The photoelectric effect . 30 4 Experimental equipment . 33 4.1 Vacuum . 33 4.2 Synchrotron radiation . 34 4.3 Laser Light . 36 4.4 The MAX laboratory and beam-line I411 . 37 4.5 Sample production . 39 4.5.1
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