We review oxygen K-edge X-ray absorption spectra of both molecules and solids. We start
with an overview of the main experimental aspects of oxygen K-edge X-ray absorption …

Intersystem crossing (ISC), formally forbidden within nonrelativistic quantum theory, is the
mechanism by which a molecule changes its spin state. It plays an important role in the …

MOLCAS/OpenMolcas is an ab initio electronic structure program providing a large set of
computational methods from Hartree–Fock and density functional theory to various …

The quantum-mechanical motion of electrons in molecules and solids occurs on the sub-
femtosecond timescale. Consequently, the study of ultrafast electronic phenomena requires …

X-ray free-electron lasers (XFELs) and table-top sources of x-rays based upon high
harmonic generation (HHG) have revolutionized the field of ultrafast x-ray atomic and …

The ultrafast photoinduced ring-opening of 1, 3-cyclohexadiene constitutes a textbook
example of electrocyclic reactions in organic chemistry and a model for photobiological …

The metal centres in metalloenzymes and molecular catalysts are responsible for the
rearrangement of atoms and electrons during complex chemical reactions, and they enable …

Conical intersections play a critical role in excited-state dynamics of polyatomic molecules
because they govern the reaction pathways of many nonadiabatic processes. However …

We present a fully analytical implementation of the core–valence separation (CVS) scheme
for the equation-of-motion (EOM) coupled-cluster singles and doubles (CCSD) method for …

The availability of X‐ray light sources with increased resolution and intensity has provided a
foundation for increasingly sophisticated experimental studies exploiting the spectroscopy of …