Themed collection XUV/X-ray light and fast ions for ultrafast chemistry

Photo-induced molecular dynamics can now be investigated using free electron lasers (FELs) whose attributes are unprecedented brightness, few femtosecond pulses duration and in the near future few hundreds of attosecond pulse duration.

Counterion sensitive photodynamics of the retinal chromophore in solution.

Radical creation after single-photon ionisation of collagen peptides induces the loss of molecules from amino-acid residue side-chains.

We investigate the multiphoton ionization of NO₂ using tunable (430–375 nm) femtosecond pulses and photoelectron–photoion coincidence momentum spectroscopy.

A time-dependent multiconfiguration self-consistent-field method for a system consisting of arbitrarily different kinds and numbers of interacting fermions and bosons.

A method for determining the resonant dynamic Stark shift (RDSS), based on wave-packet calculations of the populations of quantum states, is presented. The RDSS data are used to analyze selective multiphoton ionization of sodium.

Probing electronic coherences between 1A′′ and 1A′ in HCN induced by photoexcitation using a femtosecond UV pulse.

Short XUV pulses produce excited cationic states of benzene. Their dynamics are probed by few-cycle VIS/NIR pulses. Very fast τ ≈ 20 fs nonadiabatic processes dominate the relaxation. In the CH₃⁺ fragmentation channel a non-trivial transient behaviour is observed.

We have studied collisions between tetraphenylporphyrin cations and He or Ne at center-of-mass energies in the range 50–110 eV.

Molecular double core hole contribution to the final atomic ion fragments of N₂ when driven by an FEL pulse.

The fragmentation of the isolated 5-bromouracil (5BrU) molecule and pure and nano-hydrated 5BrU clusters induced by low energy ¹²C⁴⁺ ions has been studied.

Ultrafast dynamics and fragmentation of thymidine and thymine after ionization by attosecond extreme ultraviolet radiation studied in the time-domain.

The excitation-wavelength dependence of the intersystem crossing (ISC) dynamics of 2-thiouracil was studied in gas-phase and solution.

We study from a theoretical perspective the ionization of molecules and clusters induced by irradiation of a combined two-color laser field consisting of a train of attosecond XUV pulses in the presence of an IR field.

The adiabatic potential energy curves of the LiH molecule have been calculated. By solving the TDSE, the classical experiment of Velasco on dissociation in the ¹Π state has been explained for the first time in detail.

Photoionization of biomolecules upon interaction with an attosecond pulse leads to ultrafast charge fluctuations in the sub-femtosecond time scale. The ultrafast charge migration process in glycine, resulting from the coherent superposition of cationic states, is described using the time-dependent static-exchange DFT method.

Investigations of the collision-induced processes involving carbon ions and molecules of biological interest, in particular DNA building blocks, are crucial to model the effect of radiation on cells to improve medical treatments for cancer therapy.

This paper demonstrates how the time-dependent scattering signal of electronic wave packets in the hydrogen atom can be expressed analytically.

We present the first ab initio multi-channel photoionization calculations for NO₂ in the vicinity of the ²A₁/²B₂ conical intersection, for a range of nuclear geometries, using our newly developed set of tools based on the ab initio multichannel R-matrix method.

OCS full rotational revival dynamics induced by impulsive NIR alignment monitored by Coulomb explosion correlated fragments after S 2p excitation.

We report on studies of collisions between 3 keV Ar⁺ projectile ions and neutral targets of isolated 1,3-butadiene (C₄H₆) molecules and cold, loosely bound clusters of these molecules.

Survival probability vs. time of hot electron-excited C₆₀ at energies 10 through 70 eV.

Multiply charged ions very efficiently capture several electrons from trapped mass/charge selected protein poly-anions, producing dominantly charge-reduced proteins and small neutral losses.

Nonadiabatic effects play a very important role in controlling chemical dynamical processes.

The Coulomb explosion mechanism of a CH₂I₂ molecule is rather different to that of CH₃I. The kinetic energy of iodine ions is ∼3 times larger due to Coulomb repulsion of the two iodine ions, while that of carbon ions is almost the same for both, as indicated by the red arrows that represent kinetic energies of the atomic ions.

Prompt dissociation competes with statistical dissociation after photoexcitation of the amide chromophore.

IR and XUV pulse interaction result in modulated asymmetries of photoelectron spectra.

We calculate nonresonant inelastic electron and X-ray scattering cross sections for bound-to-bound transitions in atoms and molecules from ab initio electronic wavefunctions.

A generalized motif model to describe the stability of neutral fullerenes, covering the full range of cage sizes, starting from C₆₀, going through giant fullerenes, and ultimately leading to graphene.

Angularly-resolved photoelectron spectra for acetylene ionized by ultrashort laser pulses are calculated: these show how excited states influence electron emission.

The Jahn–Teller instability of cyclopropane contributes to dissociative double ionization processes.

The direct dynamics variational multi-configurational Gaussian (DD-vMCG) method is combined with electronic structure calculations accelerated by Graphical Processing Units (GPUs). This is used to identify GPU acceleration will have a significant effect for both ground and excited state simulations.

We present a combined experimental and theoretical study of the fragmentation of multiply-charged γ-aminobutyric acid molecules (GABA^z+, z = 2, 3) in the gas phase.

On-the-fly excited state molecular dynamics is a valuable method for studying non-equilibrium processes in excited states and is beginning to emerge as a mature approach much like its ground state counterparts.

We report a full analysis of the resonant inelastic X-ray scattering spectra of H₂O, D₂O and HDO.

Proton-induced charge transfer on HCN polymers. Charge transfer efficiency exhausted compared to cyclic biomolecules (nucleobases, sugars, cyclic prebiotic compounds).

Long range anisotropic interactions and molecular orbital symmetry rule the dynamics of an astrochemically relevant dissociative charge-exchange process.

By monitoring ionization and fragmentation after single-photon absorption, we show that an isolated collagen triple helix model is stabilized by proline hydroxylation.