Main Content

Scientific Milestone

  • Development of an atmospheric pressure version of CAIT by means of a fs-laser generated plasma (APL 2018)
  • Characterization of energy landscape of solid materials by quantification of the width of site energy distributions (Materials Today Physics 2018)
  • Measurement of higly accurate ionic work function for Li+ from solide electrolytes/electrode material (JAP 2016) , Development of a thermodynamic cycle for lithium ion batteries (LIB) by combination of ionic and electronic work function measurements of electrode materials (Coop with Jägermann/Hausbrand) (Advanced Energy Materials 2018)
  • Measurement of conductivity of an single bilayer PAH/PSS, thickness approx. 4 nm (PCCP 2016) 
  • Formation and spatially resolved analysis (ToF-SIMS, HR-FIB-TEM) of electrochemical interphase formation at the former interface between sample and electrode (Electrochimica Acta 2015, 2016) 
  • Formation of concentration depletion profiles by means of foreign ion BIIT and quantitative analysis by means of ToF-SIMS and numerical Nernst-Planck-Poisson modelling (ZPC 2012, Electrochimica Acta 2016)
  • Development of a new approach for measuring ionic conductivities and ionic diffusion coefficients by bombardment induced ion transport (BIIT) (PCCP 2011, PCCP2013, PCCP2016). This new concept is based on shining an alkali-ion beam on the surface of a sample, thus, generating a potential gradient and a particle gradient across the sample. The sample is connected to an electrode on the backside at which the current induced by the two gradients is measured. In contrast to ALL other know approaches, our approach utilizes a single sample/electrode interface (not zero, not two or more). 
  • Development of a new approach for the analysis of chirality by measuring the circular dichroism in the ion yields obtained in resonant as well as non-resonant femtosecond laser ionization (CPC2009, PCCP2011, Chirality 2012) (patent issued)
  • Control of chemical dynamics via control of the electron dynamics, either by femtosecond interferometry or by control of the carrier envelope phase (CPC 2007, JCP 2008, etc.)
  • Unifying experiments and theory in the frequency as well as in the time domain on the dynamics of photochemical processes in the HCl+ / DCl+ ion (JCP 2005, JPC2006, CP2007, etc. ). This work led to a profound understanding of these processes with special attention not only on the complementarity of time and frequency domain approach but also on the transition from kinetics to dynamics.
  • Proof of the ability to control a proton transfer reaction via the rotational angular momentum of the proton donator (ZPC2007 and JCP2010). For an endothermic reaction the cross section for proton transfer is maximized for large collision energies but small rotational angular momentum. For an exothermic reaction the cross section is maximized for small collision energies but again small rotational angular momentum.
  • Determination of the dissociation energy of a molecular ion (HCl+) with sub-rotational resolution (precision better than that of the JANAF tables) (PCCP 2002). The approach is based on observing a step function on the Lorentzian envelope of a single rotational molecular transition.
  • First demonstration of a pulsed-field-ionization electron-ion-coincidence (PFI-PEPICO) experiment employing synchrotron radiation for excitation (CPL 1996). At that time everyone else thought long-lived Rydberg states would not exist under single ionization conditions. Later we combined our PFI-PEPICO technique with the superb resolution of the chemical dynamics beam line (Cheuk Ng) leading to thermochemical data of unprecedented precision (PRL 2001). One of the intriguing aspects was an inverse born-Oppenheimer situation observed in a long-lived Rydberg state of CH4 , where the CH4+ split off a H-atom without the Rydberg electron even noticing.