Electron-Core-Hole Interaction in GaAsP

Comment on ‘‘Electron Core-Hole Interaction and Its Induced Ionic Structural Relaxation in Molecular Systems

In a recent Letter [1] Ji et al. discuss the electron corehole interaction and its induced structural relaxation in molecular systems under x-ray irradiation. They claim that both intramolecular electronic and subsequent structural relaxation effects have to be taken into account when explaining x-ray standing wave (XSW) data by densityfunctional theory (DFT). In essence, they question that XSW...

Nano-engineered electron–hole exchange interaction controls exciton dynamics in core–shell semiconductor nanocrystals

A strong electron-hole exchange interaction (EI) in semiconductor nanocrystals (NCs) gives rise to a large (up to tens of meV) splitting between optically active ('bright') and optically passive ('dark') excitons. This dark-bright splitting has a significant effect on the optical properties of band-edge excitons and leads to a pronounced temperature and magnetic field dependence of radiative de...

Effective mass of electrons and holes in bilayer graphene: Electron-hole asymmetryand electron-electron interaction

Attosecond X-ray interaction with core-hole atoms

We assume implicitly that X-rays interact with atoms in their ground state when we analyze data obtained by X-ray diffractometry or spectroscopy. Now, the success of X-ray free-electron lasers (XFEL) challenges this "common sense." A femtosecond flush of XFEL provides X-ray photons comparable to those generated by SPring-8 undulator beamlines over one second. Such high intensity X-rays may be a...

Electron core-hole interaction and its induced ionic structural relaxation in molecular systems under x-ray irradiation.

The experiments on perylene-3,4,9,10-tetracarboxylic-3,4,9,10-dianhydride and 16FCuPc on Ag(111) surfaces by the normal incidence x-ray standing wave are poorly reproduced by first-principles ground state calculations but well reproduced by considering initial- and final-state effects, which include the response of the valence electrons to screen a core hole created by x-ray photoemission and f...