Publications by Jochen Rittmann

Experimental station Bernina at SwissFEL: condensed matter physics on femtosecond time scales investigated by X-ray diffraction and spectroscopic methods

Paul Beaud, Christopher Alexander Arrell, Christoph Peter Hauri, Giulia Fulvia Mancini, Jochen Rittmann

The Bernina instrument at the SwissFEL Aramis hard X-ray free-electron laser is designed for studying ultrafast phenomena in condensed matter and material science. Ultrashort pulses from an optical laser system covering a large wavelength range can be used ...

International Union of Crystallography (IUCr)2019

Revealing hole trapping in zinc oxide nanoparticles by time-resolved X-ray spectroscopy

Majed Chergui, Wojciech Gawelda, Thomas James Penfold, Jochen Rittmann, Fabio Giacomo Santomauro

Nature Research2018

Revealing hole trapping in zinc oxide nanoparticles by time-resolved X-ray spectroscopy

Majed Chergui, Wojciech Gawelda, Thomas James Penfold, Jochen Rittmann, Fabio Giacomo Santomauro

AMER CHEMICAL SOC2018

Time-resolved Element-selective Probing of Charge Carriers in Solar Materials

Majed Chergui, Mercedes Hannelore Rittmann-Frank, Jochen Rittmann, Thomas Charles Henry Rossi, Fabio Giacomo Santomauro, Dominik Kinschel, James Michael Budarz

We review our recent results on the implementation of picosecond (ps) X-ray absorption spectroscopy to probe the electronic and geometric structure of centres formed by photoexcitation of solar materials such as TiO2 polymorphs and inorganic Cs-based perov ...

2017

Ultrafast structural dynamics of the orthorhombic distortion in the Fe-pnictide parent compound BaFe2As2

Paul Beaud, Jochen Rittmann

Using femtosecond time-resolved hard x-ray diffraction, we investigate the structural dynamics of the orthorhombic distortion in the Fe-pnictide parent compound BaFe2As2. The orthorhombic distortion analyzed by the transient splitting of the (1 0 3) Bragg ...

Amer Inst Physics2016

NO binding kinetics in myoglobin investigated by picosecond Fe K-edge absorption spectroscopy

Majed Chergui, Camelia Borca, Frederico Alves Lima, Marco Eli Reinhard, Mercedes Hannelore Rittmann-Frank, Thomas James Penfold, Jochen Rittmann, Mahsa Silatani

Diatomic ligands in hemoproteins and the way they bind to the active center are central to the protein's function. Using picosecond Fe K-edge X-ray absorption spectroscopy, we probe the NO-heme recombination kinetics with direct sensitivity to the Fe-NO bi ...

National Academy of Sciences2015

Femtosecond X-ray absorption study of electron localization in photoexcited anatase TiO2

Majed Chergui, Paul Beaud, Camelia Borca, Jochen Rittmann, Mahsa Silatani, Edoardo Baldini, Fabio Giacomo Santomauro, Patric Zimmermann

Transition metal oxides are among the most promising solar materials, whose properties rely on the generation, transport and trapping of charge carriers (electrons and holes). Identifying the latter's dynamics at room temperature requires tools that combin ...

Nature Publishing Group2015

Ultrafast Structural Dynamics of the Fe-Pnictide Parent Compound BaFe2As2

Paul Beaud, Jochen Rittmann

Using femtosecond time-resolved x-ray diffraction we investigate the structural dynamics of the coherently excited A(1g) phonon mode in the Fe-pnictide parent compound BaFe2As2. The fluence dependent intensity oscillations of two specific Bragg reflections ...

American Physical Society2015

Mapping of the Photoinduced Electron Traps in TiO2 by Picosecond X-ray Absorption Spectroscopy

Majed Chergui, Marco Eli Reinhard, Mercedes Hannelore Rittmann-Frank, Thomas James Penfold, Jochen Rittmann

Titanium dioxide (TiO2) is the most popular material for applications in solar-energy conversion and photocatalysis, both of which rely on the creation, transport, and trapping of charges (holes and electrons). The nature and lifetime of electron traps at ...

Wiley-Blackwell2014

Probing the dynamics of plasmon-excited hexanethiol-capped gold nanoparticles by picosecond X-ray absorption spectroscopy

Majed Chergui, Thomas James Penfold, Jochen Rittmann

Picosecond X-ray absorption spectroscopy (XAS) is used to investigate the electronic and structural dynamics initiated by plasmon excitation of 1.8 nm diameter Au nanoparticles (NPs) functionalised with 1-hexanethiol. We show that 100 ps after photoexcitat ...

Royal Society of Chemistry2014

Characterizing the Structure and Defect Concentration of ZnO Nanoparticles in a Colloidal Solution

Majed Chergui, Camelia Borca, Marco Eli Reinhard, Mercedes Hannelore Rittmann-Frank, Thomas James Penfold, Jochen Rittmann, Thomas Charles Henry Rossi

The structure and defect concentration of colloidal solutions of ZnO nanoparticles, synthesized by a sol gel procedure (SG-NP), as well as commercially available ZnO nanoparticles (SA-NP) are investigated by UV-vis absorption spectroscopy, transmission ele ...

Amer Chemical Soc2014

Solvent Induced Luminescence Quenching: Static and Time-Resolved X-Ray Absorption Spectroscopy of a Copper(I) Phenanthroline Complex

Majed Chergui, Olivier Christian Bräm, Ursula Röthlisberger, Ivano Tavernelli, Frederico Alves Lima, Marco Eli Reinhard, Mercedes Hannelore Rittmann-Frank, Thomas James Penfold, Lotta Susanne Karlsson, Jochen Rittmann, Gloria Capano

We present a static and picosecond X-ray absorption study at the Cu K-edge of bis(2,9-dimethyl-1,10-phenanthroline)copper(I) (Cu(dmp)(2); dmp = 2,9-dimethyl-1,10-phenanthroline) dissolved in acetonitrile and dichloromethane. The steady-state photolumi ...

Amer Chemical Soc2013