Research Interests

My main research interest is the electronic structure of transition metal clusters and coordination compounds. Specifically, I am interested into gaining insight into how manipulation of the atomic environment affects the electronic structure at the transition metal site. The controlled manipulation is achieved in clusters by varying the number of atoms and by doping or alloying of the clusters. To probe the electronic structure of cluster or molecular ions, I apply x-ray absorption spectroscopy and x-ray induced photodissociation in combination with mass spectrometry. Additionally, information on the spin and orbital magnetic moments of the ions is obtainable by exploting the x-ray magnetic circular dichroism effect.

I am also involved in the development of methods for extending the application range of x-ray spectroscopy techniques into the gas-phase. These include new methods for the preparation of molecular and atomic ions or new ion yield selective detection schemes.

A complete list of my publications as pdf can be downloaded below:

Publications

Recent publications

2024


  • Svensson, P.H.W.; Schwob, L.; Granäs, O.; Unger, I.; Björneholm, O.; Timneanu, N.; Lindblad, R.; Vieli, A.L.; Zamudio-Bayer, V.; Timm, M.; Hirsch, K.; Caleman, C.; Berholts, M.: Heavy element incorporation in nitroimidazole radiosensitizers: molecular-level insights into fragmentation dynamics. Physical Chemistry Chemical Physics 26 (2024), p. 770-779

2023


  • Ablyasova, O.S.; Guo, M.; Zamudio-Bayer, V.; Kubin, M.; Gitzinger, T.; da Silva Santos, M.; Flach, M.; Timm, M.; Lundberg, M.; Lau, J.T.; Hirsch, K.: Electronic Structure of the Complete Series of Gas-Phase Manganese Acetylacetonates by X-ray Absorption Spectroscopy. The Journal of Physical Chemistry A 127 (2023), p. 7121-7131

  • da Silva Santos, M.; Medel, R.; Flach, M.; Ablyasova, O.S.; Timm, M.; von Issendorff, B.; Hirsch, K.; Zamudio-Bayer, V.; Riedel, S.; Lau, J.T.: Exposing the Oxygen-Centered Radical Character of the Tetraoxido Ruthenium(VIII) Cation [RuO4]+. ChemPhysChem 24 (2023), p. e202300390/1-7

  • Huo, Y.; Cangahuala, M.K.E.; Zamudio-Bayer, V.; Goulart, M.; Kubin, M.; Timm, M.; Lau, J.T.; Issendorff, B.v.; Hoekstra, R.; Faraji, S.; Schlathölter, T.: A comparative laboratory study of soft X-ray-induced ionization and fragmentation of five small PAH cations. The European Physical Journal D 77 (2023), p. 181/1-11

  • Huo, Y.; Espinoza Cangahuala, M.K.; Zamudio-Bayer, V.; Goulart, M.; Kubin, M.; Timm, M.; Lau, J.T.; von Issendorff, B.; Hoekstra, R.; Faraji, S.; Schlathölter, T.: An X-ray spectroscopy study of structural stability of superhydrogenated pyrene derivatives. Monthly Notices of the Royal Astronomical Society 523 (2023), p. 865-875

  • Leroux, J.; Kotobi, A.; Hirsch, K.; Lau, T.; Ortiz-Mahecha, C.; Maksimov, D.; Meißner, R.; Oostenrijk, B.; Rossi, M.; Schubert, K.; Timm, M.; Trinter, F.; Unger, I.; Zamudio-Bayer, V.; Schwob, L.; Bari, S.: Mapping the electronic transitions of protonation sites in peptides using soft X-ray action spectroscopy. Physical Chemistry Chemical Physics 25 (2023), p. 25603-25618

  • Liu, M.; O’Reilly, D.; Schwob, L.; Wang, X.; Zamudio-Bayer, V.; Lau, J. T.; Bari, S.; Schlathölter, T.; Poully, J.-C.: Direct observation of charge, energy and H transfer between backbone and nucleobases in isolated DNA oligonucleotides. Chemistry - A European Journal 29 (2023), p. e202203481/1-9

2022


  • da Silva Santos, M.; Stüker, T.; Flach, M.; Ablyasova, O.S.; Timm, M.; von Issendorff, B.; Hirsch, K.; Zamudio-Bayer, V.; Riedel, S.; Lau, J.T.: The Highest Oxidation State of Rhodium: Rhodium(VII) in [RhO3]+. Angewandte Chemie - International Edition 61 (2022), p. e202207688/1-5

  • Delcey, M.G.; Lindblad, R.; Timm, M.; Bülow, C.; Zamudio-Bayer, V.; von Issendorff, B.; Lau, J. T.; Lundberg, M.: Soft X-ray signatures of cationic manganese-oxo systems, including a high-spin manganese(v) complex. Physical Chemistry Chemical Physics 24 (2022), p. 3598-3610

  • Flach, M.; Hirsch, K.; Timm, M.; Ablyasova, O.S.; da Silva Santos, M.; Kubin, M.; Bülow, C.; Gitzinger, T.; Issendorff, B. von; Lau, J. T.; Zamudio-Bayer, V.: Iron L-3-edge energy shifts for the full range of possible 3d occupations within the same oxidation state of iron halides. Physical Chemistry Chemical Physics 24 (2022), p. 19890-19894

  • Gopakumar, G.; Svensson, P.H. W.; Granas, O.; Brena, B.; Schwob, L.; Unger, I.; Saak, C.-M.; Timm, M.; Buelow, C.; Kubin, M.; Zamudio-Bayer, V.; Lau, J. T.; von Issendorff, B.; Abid, A.R.; Lindblad, A.; Danielsson, E.; Koerfer, E.; Caleman, C.; Bjorneholm, O.; Lindblad, R.: X-ray Induced Fragmentation of Protonated Cystine. The Journal of Physical Chemistry A 126 (2022), p. 1496–1503

  • Huo, Y.; Cangahuala, M.K. E.; Goulart, M.; Zamudio-Bayer, V.; Kubin, M.; Timm, M.; Lau, J. T.; Issendorff, B.v.; Hoekstra, R.; Faraji, S.; Schlathölter, T.: Soft-x-ray spectroscopy of coronene+ and (coronene+H)+ cations: The influence of hydrogenation on electronic structure and photofragmentation. Physical Review A 106 (2022), p. 063104/1-11

  • Lindblad, R.; Kjellsson, L.; De Santis, E.; Zamudio-Bayer, V.; Von Issendorff, B.; Sorensen, S.L.; Lau, J.T.; Hua, W.; Carravetta, V.; Rubensson, J.E.; Ågren, H.; Couto, R.C.: Experimental and theoretical near-edge x-ray-absorption fine-structure studies of NO+. Physical Review A 106 (2022), p. 042814/1-8

  • Schmitt, M.; Maylaender, M.; Heizmann, T.; Richert, S.; Buelow, C.; Hirsch, K.; Zamudio-Bayer, V.; Lau, J. T.; Krossing, I.: Isolation and Characterization of the Homoleptic Nickel(I) and Nickel(II) Bis-benzene Sandwich Cations. Angewandte Chemie - International Edition 61 (2022), p. e202211555/1-5

  • Tombers, M.; Meyer, J.; Meyer, J.; Lawicki, A.; Zamudio-Bayer, V.; Hirsch, K.; Lau, J.T.; von Issendorff, B.; Terasaki, A.; Schlathölter, T.A.; Hoekstra, R.A.; Schmidt, S.; Powell, A.K.; Kessler, E.; Prosenc, M.H.; van Wüllen, C.; Niedner-Schatteburg, G.: Mn-12-Acetate Complexes Studied as Single Molecules. Chemistry - A European Journal 28 (2022), p. e202102592/1-7

  • Wang, X.; Rathnachalam, S.; Zamudio-Bayer, V.; Bijlsma, K.; Li, W.; Hoekstra, R.; Kubin, M.; Timm, M.; von Issendorff, B.; Lau, J. T.; Faraji, S.; Schlathölter, T.: Intramolecular hydrogen transfer in DNA induced by site-selective resonant core excitation. Physical Chemistry Chemical Physics 24 (2022), p. 7815-7825

2021


  • Couto, R.C.; Hua, W.; Lindblad, R.; Kjellsson, L.; Sorensen, S.L.; Kubin, M.; Bulow, C.; Timm, M.; Zamudio-Bayer, V.; von Issendorff, B.; Soderstrom, J.; Lau, J. T.; Rubensson, J.-E.; Agren, H.; Carravetta, V.: Breaking inversion symmetry by protonation: experimental and theoretical NEXAFS study of the diazynium ion, N2H+. Physical Chemistry Chemical Physics 23 (2021), p. 17166-17176

  • Dörner, S.; Schwob, L.; Atak, K.; Schubert, K.; Boll, R.; Schlathölter, T.; Timm, M.; Bülow, C.; Zamudio-Bayer, V.; von Issendorff, B.; Lau, J.T.; Techert, S.; Bari, S.: Probing Structural Information of Gas-Phase Peptides by Near-Edge X-ray Absorption Mass Spectrometry. Journal of The American Society for Mass Spectrometry 32 (2021), p. 670-684

  • Schubert, K.; Guo, M.; Atak, K.; Dörner, S.; Bülow, C.; von Issendorff, B.; Klumpp, S.; Lau, J.T.; Miedema, P.S.; Schlathölter, T.; Techert, S.; Timm, M.; Wang, X.; Zamudio-Bayer, V.; Schwob, L.; Bari, S.: The electronic structure and deexcitation pathways of an isolated metalloporphyrin ion resolved by metal L-edge spectroscopy. Chemical Science 12 (2021), p. 3966-3976

  • Wang, X.; Rathnachalam, S.; Bijlsma, K.; Li, W.; Hoekstra, R.; Kubin, M.; Timm, M.; von Issendorff, B.; Zamudio-Bayer, V.; Lau, J.T.; Faraji, S.; Schlathölter, T.: Site-selective soft X-ray absorption as a tool to study protonation and electronic structure of gas-phase DNA. Physical Chemistry Chemical Physics 23 (2021), p. 11900-11906

2020


  • Couto, R.C.; Kjellsson, L.; Ågren, H.; Carravetta, V.; Sorensen, S.L.; Kubin, M.; Bülow, C.; Timm, M.; Zamudio-Bayer, V.; Von Issendorff, B.; Lau, J.T.; Söderström, J.; Rubensson, J.E.; Lindblad, R.: The carbon and oxygen K-edge NEXAFS spectra of CO+. Physical Chemistry Chemical Physics 22 (2020), p. 16215-16223

  • Lindblad, R.; Kjellsson, L.; Couto, R.C.; Timm, M.; Bülow, C.; Zamudio-Bayer, V.; Lundberg, M.; Von Issendorff, B.; Lau, J.T.; Sorensen, S.L.; Carravetta, V.; Ågren, H.; Rubensson, J.E.: X-Ray Absorption Spectrum of the N+2 Molecular Ion. Physical Review Letters 124 (2020), p. 203001/1-7

  • Schwob, L.; Dörner, S.; Atak, K.; Schubert, K.; Timm, M.; Bülow, C.; Zamudio-Bayer, V.; von Issendorff, B.; Lau, J.T.; Techert, S.; Bari, S.: Site-Selective Dissociation upon Sulfur L-Edge X-ray Absorption in a Gas-Phase Protonated Peptide. The Journal of Physical Chemistry Letters 11 (2020), p. 1215-1221

2019


  • Walter, M.; Vogel, M.; Zamudio-Bayer, V.; Lindblad, R.; Reichenbach, T.; Hirsch, K.; Langenberg, A.; Rittmann, J.; Kulesza, A.; Mitric, R.; Moseler, M.; Möller, T.; Issendorff, B. von; Lau, J.T.: Experimental and theoretical 2p core-level spectra of size-selected gas-phase aluminum and silicon cluster cations: chemical shifts, geometric structure, and coordination-dependent screening. Physical Chemistry Chemical Physics 21 (2019), p. 6651-6661

2018


  • Bari, S.; Egorov, D.; Jansen, T.; Boll, R.; Hoekstra, R.; Techert, S.; Zamudio-Bayer, V.; Bülow, C.; Lindblad, R.; Leistner, G.; Lawicki, A.; Hirsch, K.; Miedema, P.; von Issendorff, B.; Lau, J.T.; Schlathölter, T.: Soft X-ray Spectroscopy as a Probe for Gas-Phase Protein Structure: Electron Impact Ionization from Within. Chemistry - A European Journal 24 (2018), p. 7631-7636

  • Egorov, D.; Bari, S.; Boll, R.; Dörner, S.; Deinert, S.; Techert, S.; Hoekstra, R.; Zamudio-Bayer, V.; Lindblad, R.; Bülow, C.; Timm, M.; von Issendorff, B.; Lau, J.T.; Schlathölter, T.: Near-Edge Soft X-ray Absorption Mass Spectrometry of Protonated Melittin. Journal of The American Society for Mass Spectrometry 29 (2018), p. 2138–2151

  • Meier, S.C.; Holz, A.; Kulenkampff, J.; Schmidt, A.; Kratzert, D.; Himmel, D.; Schmitz, D.; Scheidt, E.; Scherer, W.; Bülow, C.; Timm, M.; Lindblad, R.; Akin, S.; Zamudio-Bayer, V.; von Issendorff, B.; Duncan, M.; Lau, J.T.; Krossing, I.: Access to the Bis-benzene Cobalt(I) Sandwich Cation and its Derivatives: Synthons for a "Naked" Cobalt(I) Source? Angewandte Chemie - International Edition 57 (2018), p. 9310-9314

  • Zamudio-Bayer, V.; Hirsch, K.; Langenberg, A.; Lawicki, A.; Terasaki, A.; von Issendorff, B.; Lau, T.: Large orbital magnetic moments of small, free cobalt cluster ions Co+n with n ≤ 9. Journal of Physics: Condensed Matter 30 (2018), p. 464002/1-10

2016


  • Akin, S.T.; Zamudio-Bayer, V.; Duanmu, K.; Leistner, G.; Hirsch, K.; Bülow, C.; Lawicki, A.; Terasaki, A.; von Issendorff, B.; Truhlar, D.G.; Lau, J.T.; Duncan, M.A.: Size-Dependent Ligand Quenching of Ferromagnetism in Co3(benzene)n+ Clusters Studied with X-ray Magnetic Circular Dichroism Spectroscopy. The Journal of Physical Chemistry Letters 7 (2016), p. 4568-4575

  • Zamudio-Bayer, V.; Lindblad, R.; Bülow, C.; Leistner, G.; Terasaki, A.; von Issendorff, B.; Lau, J. T.: Electronic ground state of Ni2+. The Journal of Chemical Physics 145 (2016), p. 194392/1-7

2015


  • Hirsch, K.; Zamudio-Bayer, V.; Langenberg, A.; Niemeyer, M.; Langbehn, B.; Möller, T.; Terasaki, A.; von Issendorff, B.; Lau, J. T.: Magnetic Moments of Chromium-Doped Gold Clusters: The Anderson Impurity Model in Finite Systems. Physical Review Letters 114 (2015), p. 087202/1-6

  • Hirsch, K.; Zamudio-Bayer, V.; Langenberg, A.; Vogel, M.; Rittmann, J.; Forin, S.; Möller, T.; von Issendorff, B.; Lau, J.T.: Impurity Electron Localization in Early-Transition-Metal-Doped Gold Clusters. The Journal of Physical Chemistry C 119 (2015), p. 11184-11192

  • Kasigkeit, C.; Hirsch, K.; Langenberg, A.; Möller, T.; Probst, J.; Rittmann, J.; Vogel, M.; Wittich, J.; Zamudio-Bayer, V.; von Issendorff, B.; Lau, J.T.: Higher Ionization Energies from Sequential Vacuum Ultraviolet Multiphoton Ionization of Size-Selected Silicon Cluster Cations. The Journal of Physical Chemistry C 119 (2015), p. 11148-11152

  • Zamudio-Bayer, V.; Hirsch, K.; Langenberg, A.; Kossick, M.; Ławicki, A.; Terasaki, A.; v. Issendorff, B.; Lau, J.T.: Direct observation of high-spin states in manganese dimer and trimer cations by x-ray magnetic circular dichroism spectroscopy in an ion trap. The Journal of Chemical Physics 142 (2015), p. 234301/1-6

  • Zamudio-Bayer, V.; Hirsch, K.; Langenberg, A.; Lawicki, A.; Terasaki, A.; von Issendorff, B.; Lau, J.T.: Electronic ground states of Fe2+ and Co2+ as determined by x-ray absorption and x-ray magnetic circular dichroism spectroscopy. The Journal of Chemical Physics 143 (2015), p. 244318/1-6

  • Zamudio-Bayer, V.; Hirsch, K.; Langenberg, A.; Niemeyer, M.; Vogel, M.; Lawicki, A.; Terasaki, A.; Lau, J.T.; Von Issendorff, B.: Maximum Spin Polarization in Chromium Dimer Cations as Demonstrated by X-ray Magnetic Circular Dichroism Spectroscopy. Angewandte Chemie - International Edition 54 (2015), p. 4498-4501

2014


  • Langenberg, A.; Hirsch, K.; Lawicki, A.; Zamudio-Bayer, V.; Niemeyer, M.; Chmiela, P.; Langbehn, B.; Terasaki, A.; von Issendorff, B.; Lau, J.T.: Spin and orbital magnetic moments of size-selected iron, cobalt, and nickel clusters. Physical Review B 90 (2014), p. 184420/1-14

2013


  • Zamudio-Bayer, V.; Leppert, L.; Hirsch, K.; Langenberg, A.; Rittmann, J.; Kossick, M.; Vogel, M.; Richter, R.; Terasaki, A.; Möller, T.; Issendorff, B. v.; Kümmel, S.; Lau, J.T.: Coordination-driven magnetic-to-nonmagnetic transition in manganese-doped silicon clusters. Physical Review B 88 (2013), p. 115425/1-6

2012


  • Hirsch, K.; Zamudio-Bayer, V.; Rittmann, J.; Langenberg, A.; Vogel, M.; Möller, T.; v. Issendorff, B.; Lau, J.T.: Initial- and final-state effects on screening and branching ratio in 2p x-ray absorption of size-selected free 3d transition metal clusters. Physical Review B 86 (2012), p. 165402/1-11

  • Niemeyer, M.; Hirsch, K.; Zamudio-Bayer, V.; Langenberg, A.; Vogel, M.; Kossick, M.; Ebrecht, C.; Egashira, K.; Terasaki, A.; Möller, T.; von Issendorff, B.; Lau, J.T.: Spin Coupling and Orbital Angular Momentum Quenching in Free Iron Clusters. Physical Review Letters 108 (2012), p. 057201/1-5

  • Vogel, M.; Kasigkeit, C.; Hirsch, K.; Langenberg, A.; Rittmann, J.; Zamudio-Bayer, V.; Kulesza, A.; Mitric, R.; Möller, T.; v. Issendorff, B.; Lau, J.T.: 2p core-level binding energies of size-selected free silicon clusters: Chemical shifts and cluster structure. Physical Review B 85 (2012), p. 195454/1-5

  • Zamudio-Bayer, V.; Ameseder, F.; Langenberg, A.; Rittmann, J.; Vogel, M.; Möller, T.; v. Issendorff, B.; Lau, J.T.: 2p x-ray absorption of free transition-metal cations across the 3d transition elements: Calcium through copper. Physical Review A 85 (2012), p. 062501/1-9

2011


  • Lau, J.T.; Vogel, M.; Langenberg, A.; Hirsch, K.; Rittmann, J.; Zamudio-Bayer, V.; Möller, T.; von Issendorff, B.: Communication: Highest occupied molecular orbital-lowest unoccupied molecular orbital gaps of doped silicon clusters from core level spectroscopy. The Journal of Chemical Physics 134 (2011), p. 041102/1-3