A new scientific frontier opened in 2009 with the start of operations of the world's first x-ray
free-electron laser (FEL), the Linac Coherent Light Source (LCLS), at SLAC National …

The past two decades have seen rapid developments in short-pulse X-ray sources, which
have enabled the study of nuclear and electronic dynamics by ultrafast X-ray spectroscopies …

Following structural dynamics in real time is a fundamental goal towards a better
understanding of chemical reactions. Recording snapshots of individual molecules with …

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 …

A variety of organisms have evolved mechanisms to detect and respond to light, in which the
response is mediated by protein structural changes after photon absorption. The initial step …

The ultrafast light-activated electrocyclic ring-opening reaction of 1, 3-cyclohexadiene is a
fundamental prototype of photochemical pericyclic reactions. Generally, these reactions are …

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

Molecular orbital framework is of central importance in chemistry. Often used by chemists
and physicists to gain insight into molecular properties, Hartree–Fock or Kohn–Sham …

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

Simultaneous observation of nuclear and electronic motion is crucial for a complete
understanding of molecular dynamics in excited electronic states. It is challenging for a …