Publications related to Time-resolved photoelectron spectroscopy of adenine and adenosine in aqueous solution

Characterizing Conical Intersections in DNA/RNA Nucleobases with Multiconfigurational Wave Functions of Varying Active Space Size

We characterize the photochemically relevant conical intersections between the lowest-lying accessible electronic excited states of the different DNA/RNA nucleobases using Cholesky decomposition-based complete active space self-consistent field (CASSCF) al ...

Amer Chemical Soc2023

Selectively permeable microcapsules

Chuen-Ru Li

Microcapsules are appealing containers for delivering active ingredients, such as drugs and cosmetics, or conducting chemical and biological reactions on a small scale. To control the timing and location of release of these encapsulants, the shells of micr ...

EPFL2023

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

Functional and Computational Genomics Reveal Unprecedented Flexibility in Stage-Specific Toxoplasma Metabolism

Vassily Hatzimanikatis, Damien Lionel Nicolas, Dominique Soldati-Favre, Anush Chiappino-Pepe, Aarti Krishnan, Matteo Lunghi

To survive and proliferate in diverse host environments with varying nutrient availability, the obligate intracellular parasite Toxoplasma gondii reprograms its metabolism. We have generated and curated a genome-scale metabolic model (iTgo) for the fast-re ...

CELL PRESS2020

Shear Stress-Responsive Polymersome Nanoreactors Inspired by the Marine Bioluminescence of Dinoflagellates

Esther Amstad, Antoine Claude Jean Vian

Some marine plankton called dinoflagellates emit light in response to the movement of surrounding water, resulting in a phenomenon called milky seas or sea sparkle. The underlying concept, a shear-stress induced permeabilisation of biocatalytic reaction co ...

Wiley-VCH Verlag GmbH2021

Electronic Relaxation Dynamics of UV-Photoexcited 2-Aminopurine-Thymine Base Pairs in Watson-Crick and Hoogsteen Conformations

Rebecca Ann Ingle, Hugo Jean Baptiste Marroux

The fluorescent analogue 2-aminopurine (2AP) of the canonical nucleobase adenine (6-aminopurine) base-pairs with thymine (T) without disrupting the helical structure of DNA. It therefore finds frequent use in molecular biology for probing DNA and RNA struc ...

AMER CHEMICAL SOC2019

Spin polarization and attosecond time delay in photoemission from solids

Mauro Fanciulli

In the photoemission process electrons are emitted from a solid upon excitation with UV light. From the measurement of their energy and momentum, angle-resolved photoemission spectroscopy (ARPES) allows to reconstruct the electronic properties of the solid ...

EPFL2018

Ultrafast Photoelectron Spectroscopy of Liquid Samples

José Javier Pancracio Ojeda Andara

This thesis focuses on the commissioning and characterization of HARMONIUM, an ultrafast tunable EUV source based on high-harmonic generation for performing photoelectron spectroscopy of liquids. In ultrafast photoelectron spectroscopy a short pump pulse i ...

EPFL2016

First-Principles Photoemission Spectroscopy of DNA and RNA Nucleobases from Koopmans-Compliant Functionals

Nicola Marzari, Giovanni Borghi, Andrea Ferretti

The need to interpret ultraviolet photoemission data strongly motivates the refinement of first-principles techniques that are able to accurately predict spectral properties. In this work, we employ Koopmans-compliant functionals, constructed to enforce pi ...

Amer Chemical Soc2016

Harmonium: A pulse preserving source of monochromatic extreme ultraviolet (30–110 eV) radiation for ultrafast photoelectron spectroscopy of liquids

Majed Chergui, Frank van Mourik, Christopher Alexander Arrell, Hua Zhang, Lars-Hendrik Mewes, José Javier Pancracio Ojeda Andara, Jakob Grilj

A tuneable repetition rate extreme ultraviolet source (Harmonium) for time resolved photoelectron spectroscopy of liquids is presented. High harmonic generation produces 30-110 eV photons, with fluxes ranging from similar to 2 x 10(11) photons/s at 36 eV t ...

Amer Inst Physics2016

First-Principles Photoemission Spectroscopy and Orbital Tomography in Molecules from Koopmans-Compliant Functionals

Nicola Marzari, Giovanni Borghi, Andrea Ferretti

The determination of spectral properties from first principles can provide powerful connections between microscopic theoretical predictions and experimental data, but requires complex electronic-structure formulations that fall outside the domain of applic ...

Amer Physical Soc2015

On-the-fly ab initio semiclassical dynamics of floppy molecules: Absorption and photoelectron spectra of ammonia

Marius Wehrle, Jiri Vanicek, Solène Oberli

We investigate the performance of on-the-fly ab initio (OTF-AI) semiclassical dynamics combined with the thawed Gaussian approximation (TGA) for computing vibrationally resolved absorption and photoelectron spectra. Ammonia is used as a prototype of floppy ...

American Chemical Society2015

Photophysics and Photochemistry of a DNA–Protein Cross-Linking Model: A Synergistic Approach Combining Experiments and Theory

Ursula Röthlisberger, Ivano Tavernelli, Sara Bonella, Mohammadhassan Valadan

The photophysical and photochemical properties of 5-benzyluracil and 5,6-benzyluracil, the latter produced by photocyclization of the former through irradiation with femtosecond UV laser pulses, are investigated both experimentally and theoretically. The a ...

2014

Femtosecond photoelectron and photoion spectrometer with vacuum ultraviolet probe pulses

Jakob Grilj

We describe a femtosecond photoelectron and photoion spectroscopy setup using a simple, novel way to produce a vacuum ultraviolet (VUV) probe pulse. We isolate the femtosecond VUV pulse from a high harmonic continuum by using the bandpass characteristics o ...

Elsevier2014

A simple electron time-of-flight spectrometer for ultrafast vacuum ultraviolet photoelectron spectroscopy of liquid solutions

Majed Chergui, Frank van Mourik, Christopher Alexander Arrell, José Javier Pancracio Ojeda Andara

We present a simple electron time of flight spectrometer for time resolved photoelectron spectroscopy of liquid samples using a vacuum ultraviolet (VUV) source produced by high-harmonic generation. The field free spectrometer coupled with the time-preservi ...

Amer Inst Physics2014

Controlling a Single DNA Molecule in an Electric Field by Means of In Situ Atomic Force Microscopy

Giovanni Dietler, Jae Sun Jeong

DNA is the bio-polymer containing the genetic information needed for the development and functioning for all living organisms. It has a polymeric structure consisting of units called nucleotides, each consisting of a non-polar, hydrophobic interior (the ba ...

Electrochemical Society2012

A spin- and angle-resolving photoelectron spectrometer

Martin Mansson

A new type of hemispherical electron energy analyzer that permits angle and spin resolved photoelectron spectroscopy has been developed. The analyzer permits standard angle resolved spectra to be recorded with a two-dimensional detector in parallel with sp ...

2010

Binding of Organometallic Ruthenium(II) Anticancer Compounds to Nucleobases: A Computational Study

Ursula Röthlisberger, Ivano Tavernelli, Christian Gossens

The reaction of the anticancer compound (eta(6)-benzene)Ru(en)(OH2) (1) toward the nucleobases guanine, adenine, and cytosine is studied computationally using DFT/BP86 calculations. The aqua leaving group of such compounds is known to undergo ligand ...

2009

VUV-induced radiation ageing processes in CsI photocathodes studied by microscopy and spectroscopy techniques

Pranav Garg

CsI thin film photocathodes of 600 nm thickness deposited on polished Al surfaces by resistive evaporation technique were studied by angle-resolved X-ray photoelectron spectroscopy (ARXPS), before and after UV-irradiation under vacuum. It is shown that the ...

2009

Physical properties and interactions of biomolecules : an atomic force microscopy study

Mélanie Favre

The aim of this thesis was to explore the statistical physics and the mechanical properties of individual biomolecules, to study their interactions, and to develop new techniques based on atomic force microscopy (AFM). First, we exploit the high resolution ...

EPFL2008