Recherche

Afficher tous les résultats pour

Accueil

Concept

Diagramme de Jablonski

Science de la nature
Chimie
Chimie physique
Spectroscopie

À propos
Confidentialité
Mentions légales

Graph Chatbot

Publications associées (32)

Fragmentation mechanism of UV-excited peptides in the gas phase

Thomas Rizzo, Oleg Boyarkine, Michael Zachary Kamrath, Aleksandra Zabuga

We present evidence that following near-UV excitation, protonated tyrosine- or phenylalanine–containing peptides undergo intersystem crossing to produce a triplet species. This pathway competes with direct dissociation from the excited electronic state and ...

American Institute of Physics2014

Structural Melting of an Amino Acid Dimer upon Intersystem Crossing

Thomas Rizzo, Ulrich Lorenz

We present a spectroscopic investigation of the excited-state dynamics of the phenylalanine (Phe)/serine (Ser) protonated dimer in the gas phase. Using an ultraviolet (UV) laser pulse, we promote individual isomers to the S1 state and probe their fate with ...

Amer Chemical Soc2014

Ultrafast electronic and vibrational relaxations in mixed-ligand dithione-dithiolato Ni, Pd, and Pt complexes

Majed Chergui, Frank van Mourik, Andrea Cannizzo, Ahmad Odeh

Ultrafast excited-state dynamics of planar Pt, Pd, and Ni dithione-dithiolato complexes were investigated by transient absorption spectroscopy on the femtosecond-picosecond timescale. All studied complexes show a common photobehaviour, although individual ...

Royal Society of Chemistry2014

A Vibronic Coupling Hamiltonian to Describe the Ultrafast Excited State Dynamics of a Cu(I)-Phenanthroline Complex

Ursula Röthlisberger, Ivano Tavernelli, Thomas James Penfold, Gloria Capano

We present a model Hamiltonian to study the nonadiabatic dynamics of photoexcited Cu(dmp)(2), (dmp = 2,9-dimethyl-1,10-phenanthroline). The relevant normal modes, identified by the magnitude of the first order coupling constants, correspond closely to ...

2014

Dynamics of UV-excited, protonated peptides in the gas phase

Aleksandra Zabuga

The scope of this thesis is the electronically excited state dynamics of protonated peptides and their photofragmentation mechanism. UV radiation induces fragmentation of biological molecules and might cause various diseases, such as cataracts or skin canc ...

EPFL2014

Ultrafast Relaxation Dynamics of Osmium-Polypyridine Complexes in Solution

Mohammad Khaja Nazeeruddin, Majed Chergui, Andrea Cannizzo, Olivier Christian Bräm

We present steady-state absorption and emission spectroscopy and femtosecond broadband photoluminescence up-conversion spectroscopy studies of the electronic relaxation of Os(dmbp)(3) (Os1) and Os(bpy)(2)(dpp) (Os2) in ethanol, where dmbp is 4,4'-dimethyl- ...

American Chemical Society2013

Communication: Angular momentum alignment and fluorescence polarization of alkali atoms photodetached from helium nanodroplets

The theory of photofragments angular momentum polarization is applied to the photodetachment of an electronically excited alkali atom from a helium nanocluster (N = 200). The alignment of the electronic angular momentum of the bare excited alkali atoms pro ...

Amer Inst Physics2013

Charge transfer relaxation in donor–acceptor type conjugated materials

Ursula Röthlisberger, Natalie Renuka Banerji, Mariateresa Scarongella, Andrey Laktionov

The development of conjugated materials bearing electron-rich and electron-poor units along their backbone introduces new possibilities to control functionality for organic electronic applications through charge transfer character in ground and excited sta ...

Royal Society of Chemistry2013

Re and Br X-ray Absorption Near-Edge Structure Study of the Ground and Excited States of [ReBr(CO)(3)(bpy)] Interpreted by DFT and TD-DFT Calculations

Amal El Nahhas, Renske Marjan van der Veen

X-ray absorption spectra of fac-[ReBr(CO)(3)(bpy)] near the Re L-3- and Br K-edges were measured in a steady-state mode as well as time-resolved at 630 ps after 355 nm laser pulse excitation. Relativistic spin-orbit time-dependent density functional theory ...

American Chemical Society2013

Polychromatic femtosecond fluorescence studies of metal-polypyridine complexes in solution

Majed Chergui, Andrea Cannizzo, Olivier Christian Bräm, Ahmed Maher Fahmy El-Zohry

Femtosecond-resolved broadband fluorescence studies are reported for M(bpy)(3) (M = Fe, Ru), RuN3 and RuN719 complexes in solution. We investigated the pump wavelength dependence of the fluorescence of aqueous Fe(bpy)(3) and the solvent and li ...

2012

Quantum dynamics study of the competing ultrafast intersystem crossing and internal conversion in the "channel 3" region of benzene

Thomas James Penfold

Time-resolved photoelectron spectroscopy can obtain detailed information about the dynamics of a chemical process on the femtosecond timescale. The resulting signal from such detailed experiments is often difficult to analyze and therefore theoretical calc ...

American Institute of Physics2012

Ln(III)-cored complexes based on boron dipyrromethene (Bodipy) ligands for NIR emission

Jean-Claude Bünzli

Two Bodipy-based chromophores have been synthesized, which bear two methoxyphenyl substituents in the 1,7 positions and either hydrogen (L1) or bromine (L2) atoms in the 2,6 positions, with the aim of testing their ability to sensitize the luminescence of ...

2012

Page 2 sur 2