Publications de Benjamin Bauer

Exciton decay mechanism in DNA single strands: back-electron transfer and ultrafast base motions

Majed Chergui, Rahul Sharma, Malte Oppermann, Benjamin Bauer

The photochemistry of DNA systems is characterized by the ultraviolet (UV) absorption of pi-stacked nucleobases, resulting in exciton states delocalized over several bases. As their relaxation sensitively depends on local stacking conformations, disentangl ...

ROYAL SOC CHEMISTRY2022

Electronic and structural dynamics in DNA single strands

Benjamin Bauer

The absorption, conversion and transport of electronic energy in molecular aggregates is at the heart of many important natural and artificial photochemical systems, including organic solar cell materials, photosynthetic light-harvesting complexes and DNA ...

EPFL2021

Slow Charge Carrier Relaxation in Gold Nanoparticles

Majed Chergui, Thomas Charles Henry Rossi, Malte Oppermann, Lars-Hendrik Mewes, Lijie Wang, Benjamin Bauer, Davood Zare

We report on ultrafast transient absorption (TA) studies of surface plasmon-excited similar to 25 nm-diameter Au nanoparticles in solution, monitoring the response of the surface plasmon resonance in the visible region (1.7-3.0 eV) and that of the inter- a ...

AMER CHEMICAL SOC2020

Exciton dynamics in DNA oligomers studied by broadband deep-UV transient absorption spectroscopy

Majed Chergui, Malte Oppermann, Benjamin Bauer

We report broadband transient absorption measurements of adenine strands in the deep-UV (250-370 nm). By varying the strand length we resolve the interplay between inter-base stacking and exciton formation and dynamics in DNA oligomers. ...

E D P SCIENCES2019

Ultrafast broadband circular dichroism in the deep ultraviolet

Majed Chergui, Thomas Charles Henry Rossi, Malte Oppermann, Benjamin Bauer, Jérôme Lacour

The measurement of chirality and its temporal evolution are crucial for the understanding of a large range of biological functions and chemical reactions. Steady-state circular dichroism (CD) is a standard analytical tool for measuring chirality in chemist ...

OPTICAL SOC AMER2019

Broad-Band Ultraviolet CD Spectroscopy of Ultrafast Peptide Backbone Conformational Dynamics

Majed Chergui, Malte Oppermann, Benjamin Bauer

The far-UV spectral window widely used for the conformational analysis of biomolecules is not easily covered with broad-band lasers. This has made it difficult to use circular dichroism (CD) spectroscopy to directly follow fast structure changes. By combin ...

AMER CHEMICAL SOC2019

Toward time-resolved laser T-jump/X-ray probe spectroscopy in aqueous solutions

Majed Chergui, Giulia Fulvia Mancini, Camila Bacellar Cases Da Silveira, Dominik Kinschel, Oliviero Cannelli, Rebecca Ann Ingle, Benjamin Bauer

Most chemical and biochemical reactions in nature and in industrial processes are driven by thermal effects that bring the reactants above the energy barrier for reaction. In aqueous solutions, this process can also be triggered by the laser driven tempera ...

2019

The LOUVRE Laboratory: State-of-the-Art Ultrafast Ultraviolet Spectroscopies for Molecular and Materials Science

Majed Chergui, Natalia Nagornova, Frank van Mourik, Edoardo Baldini, Thomas Charles Henry Rossi, Malte Oppermann, Tania Palmieri, Lars-Hendrik Mewes, Benjamin Bauer, Aurelio Oriana

We describe the facilities for ultraviolet studies in the femtosecond to nanosecond time domain. These facilities consist of: i) a set-up for deep-ultraviolet spectroscopy in the 260–380 nm range in both pump and probe pulses for transient absorption/refle ...

2017

Introduction of oxygen vacancies and fluorine into TiO2 nanoparticles by co-milling with PTFE

Vincent Laporte, Benjamin Bauer

Solid-state processes of introducing oxygen vacancies and transference of fluorine to n-TiO2 nanoparticles by co-milling with poly(tetrafluoroethylene) (PTFE) powder were examined by diffuse reflectance spectroscopy (DRS) of UV, visual, near- and mid-IR re ...

2012