@phdthesis{Schroeder2016, author = {Schr{\"o}der, Henning}, title = {Ultrafast electron dynamics in Fe(CO)5 and Cr(CO)6}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-94589}, school = {Universit{\"a}t Potsdam}, pages = {v, 87}, year = {2016}, abstract = {In this thesis, the two prototype catalysts Fe(CO)₅ and Cr(CO)₆ are investigated with time-resolved photoelectron spectroscopy at a high harmonic setup. In both of these metal carbonyls, a UV photon can induce the dissociation of one or more ligands of the complex. The mechanism of the dissociation has been debated over the last decades. The electronic dynamics of the first dissociation occur on the femtosecond timescale. For the experiment, an existing high harmonic setup was moved to a new location, was extended, and characterized. The modified setup can induce dynamics in gas phase samples with photon energies of 1.55eV, 3.10eV, and 4.65eV. The valence electronic structure of the samples can be probed with photon energies between 20eV and 40eV. The temporal resolution is 111fs to 262fs, depending on the combination of the two photon energies. The electronically excited intermediates of the two complexes, as well as of the reaction product Fe(CO)₄, could be observed with photoelectron spectroscopy in the gas phase for the first time. However, photoelectron spectroscopy gives access only to the final ionic states. Corresponding calculations to simulate these spectra are still in development. The peak energies and their evolution in time with respect to the initiation pump pulse have been determined, these peaks have been assigned based on literature data. The spectra of the two complexes show clear differences. The dynamics have been interpreted with the assumption that the motion of peaks in the spectra relates to the movement of the wave packet in the multidimensional energy landscape. The results largely confirm existing models for the reaction pathways. In both metal carbonyls, this pathway involves a direct excitation of the wave packet to a metal-to-ligand charge transfer state and the subsequent crossing to a dissociative ligand field state. The coupling of the electronic dynamics to the nuclear dynamics could explain the slower dissociation in Fe(CO)₅ as compared to Cr(CO)₆.}, language = {en} } @article{KunnusZhangDelceyetal.2016, author = {Kunnus, Kristjan and Zhang, Wenkai and Delcey, Mickael G. and Pinjari, Rahul V. and Miedema, Piter S. and Schreck, Simon and Quevedo, Wilson and Schr{\"o}der, Henning and F{\"o}hlisch, Alexander and Gaffney, Kelly J. and Lundberg, Marcus and Odelius, Michael and Wernet, Philippe}, title = {Viewing the Valence Electronic Structure of Ferric and Ferrous Hexacyanide in Solution from the Fe and Cyanide Perspectives}, series = {The journal of physical chemistry : B, Condensed matter, materials, surfaces, interfaces \& biophysical chemistry}, volume = {120}, journal = {The journal of physical chemistry : B, Condensed matter, materials, surfaces, interfaces \& biophysical chemistry}, publisher = {American Chemical Society}, address = {Washington}, issn = {1520-6106}, doi = {10.1021/acs.jpcb.6b04751}, pages = {7182 -- 7194}, year = {2016}, abstract = {The valence-excited states of ferric and ferrous hexacyanide ions in aqueous solution were mapped by resonant inelastic X-ray scattering (RIXS) at the Fe L-2,L-3 and N K edges. Probing of both the central Fe and the ligand N atoms enabled identification of the metal-and ligand-centered excited states, as well as ligand-to-metal and metal-to-ligand charge-transfer excited states. Ab initio calculations utilizing the RASPT2 method were used to simulate the Fe L-2,L-3-edge RIXS spectra and enabled quantification of the covalencies of both occupied and empty orbitals of pi and sigma symmetry. We found that pi back-donation in the ferric complex is smaller than that in the ferrous complex. This is evidenced by the relative amounts of Fe 3d character in the nominally 2 pi CN- molecular orbital of 7\% and 9\% in ferric and ferrous hexacyanide, respectively. Utilizing the direct sensitivity of Fe L-3-edge RIXS to the Fe 3d character in the occupied molecular orbitals, we also found that the donation interactions are dominated by sigma bonding. The latter was found to be stronger in the ferric complex, with an Fe 3d contribution to the nominally 5 sigma CN- molecular orbitals of 29\% compared to 20\% in the ferrous complex. These results are consistent with the notion that a higher charge at the central metal atom increases donation and decreases back-donation.}, language = {en} } @article{MitznerRehanekKernetal.2013, author = {Mitzner, Rolf and Rehanek, Jens and Kern, Jan and Gul, Sheraz and Hattne, Johan and Taguchi, Taketo and Alonso-Mori, Roberto and Tran, Rosalie and Weniger, Christian and Schr{\"o}der, Henning and Quevedo, Wilson and Laksmono, Hartawan and Sierra, Raymond G. and Han, Guangye and Lassalle-Kaiser, Benedikt and Koroidov, Sergey and Kubicek, Katharina and Schreck, Simon and Kunnus, Kristjan and Brzhezinskaya, Maria and Firsov, Alexander and Minitti, Michael P. and Turner, Joshua J. and M{\"o}ller, Stefan and Sauter, Nicholas K. and Bogan, Michael J. and Nordlund, Dennis and Schlotter, William F. and Messinger, Johannes and Borovik, Andrew S. and Techert, Simone and de Groot, Frank M. F. and F{\"o}hlisch, Alexander and Erko, Alexei and Bergmann, Uwe and Yachandra, Vittal K. and Wernet, Philippe and Yano, Junko}, title = {L-edge x-ray absorption spectroscopy of dilute systems relevant to metalloproteins using an X-ray free-electron laser}, series = {The journal of physical chemistry letters}, volume = {4}, journal = {The journal of physical chemistry letters}, number = {21}, publisher = {American Chemical Society}, address = {Washington}, issn = {1948-7185}, doi = {10.1021/jz401837f}, pages = {3641 -- 3647}, year = {2013}, abstract = {L-edge spectroscopy of 3d transition metals provides important electronic structure information and has been used in many fields. However, the use of this method for studying dilute aqueous systems, such as metalloenzymes, has not been prevalent because of severe radiation damage and the lack of suitable detection systems. Here we present spectra from a dilute Mn aqueous solution using a high-transmission zone-plate spectrometer at the Linac Coherent Light Source (LCLS). The spectrometer has been optimized for discriminating the Mn L-edge signal from the overwhelming 0 K-edge background that arises from water and protein itself, and the ultrashort LCLS X-ray pulses can outrun X-ray induced damage. We show that the deviations of the partial-fluorescence yield-detected spectra from the true absorption can be well modeled using the state-dependence of the fluorescence yield, and discuss implications for the application of our concept to biological samples.}, language = {en} } @misc{CostardStadieRitteretal.2011, author = {Costard, Sylvia and Stadie, Nicole and Ritter, Christiane and Moll, Kristina and Landerl, Karin and Kohnen, Saskia and Kentner, Gerrit and Bethmann, Anja and Scheich, Henning and Brechmann, Andr{\´e} and De Kok, D{\"o}rte and Berger, Frauke and Sticher, Heike and Czepluch, Christine and M{\"a}tzener, Flurina and Wilmes, Stefanie and Hadert, Sandra and Frank, Ulrike and M{\"a}der, Mark and Westermann, Antje and Meinusch, Miriam and Neumann, Sandra and D{\"u}sterh{\"o}ft, Stefanie and Posse, Dorothea and Puritz, Caroline and Seidl, Rainer Ottis and Etzien, Maria and Machleb, Franziska and Lorenz, Antje and H{\"o}ger, Maria and Schr{\"o}der, Astrid and Busch, Tobias and Heide, Judith and Tagoe, Tanja and Watermeyer, Melanie and H{\"o}hle, Barbara and Kauschke, Christina}, title = {Spektrum Patholinguistik = Schwerpunktthema: Lesen lernen: Diagnostik und Therapie bei St{\"o}rungen des Leseerwerbs}, number = {4}, editor = {Hanne, Sandra and Fritzsche, Tom and Ott, Susan and Adelt, Anne}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, organization = {Verband f{\"u}r Patholinguistik e. V. (vpl)}, isbn = {978-3-86956-145-5}, issn = {1869-3822}, doi = {10.25932/publishup-5155}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-53146}, year = {2011}, abstract = {Am 20. November 2010 fand an der Universit{\"a}t Potsdam das 4. Herbsttreffen Patholinguistik statt. Die Konferenzreihe wird regelm{\"a}ßig seit 2007 vom Verband f{\"u}r Patholinguistik e.V. (vpl) durchgef{\"u}hrt. Der vorliegende Tagungsband ver{\"o}ffentlicht die Hauptvortr{\"a}ge des Herbsttreffens zum Thema "Lesen lernen: Diagnostik und Therapie bei St{\"o}rungen des Leseerwerbs". Des Weiteren sind die Beitr{\"a}ge promovierender bzw. promovierter PatholinguistInnen sowie der Posterpr{\"a}sentationen enthalten.}, language = {de} } @misc{KlannDeliusKauschkeGluecketal.2008, author = {Klann-Delius, Gisela and Kauschke, Christina and Gl{\"u}ck, Christian W. and Schr{\"o}der, Astrid and Lorenz, Antje and Domahs, Frank and Grande, Marion and Domahs, Ulrike and Frankenberg, Jenny v. and Wahl, Michael and De Kok, D{\"o}rte and Stadie, Nicole and Machleb, Franziska and Manz, Katrin and Frank, Ulrike and Sperlich, Kathrin and Vauth, Friederike and Hampel, Pamela and M{\"a}der, Mark and Sticher, Heike and Bethmann, Anja and Fischenich, Andrea and Scheich, Henning and Brechmann, Andr{\´e} and Peschke, Claudia and Ziegler, Wolfram and Kappes, Juliane and Baumg{\"a}rtner, Annette and Sonntag, Kristin and Bartels, Luise and Heide, Judith and Meinunger, Andr{\´e} and Burchert, Frank and Bohn, Christiane and Kliegl, Reinhold and Gottal, Stephanie and Berendes, Karin and Grabherr, Britta and Schneeberg, Jennifer and Wittler, Marion and Ptok, Martin and Sallat, Stephan}, title = {Spektrum Patholinguistik = Schwerpunktthema: der Erwerb von Lexikon und Semantik: Meilensteine, St{\"o}rungen und Therapie ; Tagungsband zum 1. Herbsttreffen Patholinguistik, 24. November 2007}, number = {1}, editor = {Wahl, Michael and Michael, Judith and Hanne, Sandra}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, organization = {Verband f{\"u}r Patholinguistik e. V. (vpl)}, issn = {1869-3822}, doi = {10.25932/publishup-1719}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18688}, year = {2008}, abstract = {Der vorliegende Tagungsband enth{\"a}lt alle Beitr{\"a}ge des 1. Herbsttreffens Patholinguistik, das am 24.11.2007 an der Universit{\"a}t Potsdam stattgefunden hat. Sowohl die drei Hauptvortr{\"a}ge zum Thema „Der Erwerb von Lexikon und Semantik - Meilensteine, St{\"o}rungen und Therapie" als auch die Kurzvortr{\"a}ge promovierter Patholinguisten sind ausf{\"u}hrlich dokumentiert. Außerdem enth{\"a}lt der Tagungsband die Abstracts der pr{\"a}sentierten Poster.}, language = {de} }