Related papers: Oxygen diffusion and reactivity at low temperature…
Water is abundantly present in the Universe. It is the main component of interstellar ice mantles and a key ingredient for life. Water in space is mainly formed through surface reactions. Three formation routes have been proposed in the…
The reaction N(4S) + NO -> O(3P) + N2 plays a pivotal role in the conversion of atomic to molecular nitrogen in dense interstellar clouds and in the atmosphere. Here we report a joint experimental and computational investigation of the N +…
We have developed a model for molecular hydrogen formation under astrophysically relevant conditions. This model takes fully into account the presence of both physisorbed and chemisorbed sites on the surface, allows quantum mechanical…
Oxygen atom addition and insertion reactions may provide a pathway to chemical complexity in ices that are too cold for radicals to diffuse and react. We have studied the ice-phase reactions of photo-produced oxygen atoms with C2…
The transport of H adatoms across oxide supports plays an important role in many catalytic reactions. We investigate the dynamics of H/Fe3O4(001) between 295 and 382 K. By scanning tunneling microscopy at frame rates of up to 19.6 fps, we…
Understanding the atomic mechanism of low-temperature CO oxidation on a heterogeneous catalyst is challenging. We performed density functional theory (DFT) calculations to identify the surface structure and reaction mechanism responsible…
The mobility of atoms, molecules and radicals in icy grain mantles regulate ice restructuring, desorption, and chemistry in astrophysical environments. Interstellar ices are dominated by H2O, and diffusion on external and internal (pore)…
The interactions of atomic and molecular hydrogen with bare interstellar dust grain surfaces are important for understanding H2 formation at relatively high temperatures (>20 K). We investigate the diffusion of physisorbed H atoms and the…
The oxidation of NO molecules on epoxy-functionalized highly oriented pyrolytic graphite, thermalized at 300 K, was studied by means of ab initio molecular dynamics (AIMD) calculations. Four collision energies and two different orientations…
The reaction dynamics of H$_2$COO to form linear HCOOH and dioxirane as first steps for OH-elimination is quantitatively investigated. Using a machine learned potential energy surface at the CASPT2/aug-cc-pVTZ level of theory vibrational…
We present a density-functional theory study addressing the energetics and electronic structure properties of isolated oxygen adatoms at the SrTiO3(001) surface. Together with a surface lattice oxygen atom, the adsorbate is found to form a…
In this work, we present an off-lattice Monte Carlo model of accretion and migration of hydrogen atoms on a rough surface of carbon dust grain. The migration of physisorbed atoms by means of thermal diffusion and quantum tunnelling through…
Rate constants for the N + C2 reaction have been measured in a continuous supersonic flow reactor over the range 57 K to 296 K by the relative rate technique employing the N + OH - H + NO reaction as a reference. Excess concentrations of…
Molecular beam experiments that use low-temperature bolometers as (energy-) detectors are well suited to the study of physisorption and recombination of hydrogen on low-temperature surfaces. Experiments where this technique is combined with…
The energy to desorb atomic oxygen from an interstellar dust grain surface, $E_{\rm des}$, is an important controlling parameter in gas-grain models; its value impacts the temperature range over which oxygen resides on a dust grain.…
An atomistic study of the order-effect occurring in Li$_{x}$CoO$_{2}$ at $x=0.5$ is presented and an explanation for the computationally and experimentally observed dip in the Li diffusivity is proposed. Configurations where a single…
The thermal growth of silicon oxide films on Si in dry O2 is modelled as a dynamical system, assuming that it is basically a diffusion-reaction phenomenon. Relevant findings of the last decade are incorporated, as structure and composition…
Density-functional theory calculations are performed to investigate hydrogen transport in the proton conductor BaSnO$_3$. Structural optimizations in the stable and saddle point configurations for transfer and reorientation allow…
Even though water is the main constituent in interstellar icy mantles, its chemical origin is not well understood. Three different formation routes have been proposed following hydrogenation of O, O2, or O3, but experimental evidence is…
Improving reactivity on an insulating surface is crucial due to their important applications in surface catalytic reactions. In this work, we carried out first-principles calculations to investigate the adsorption of O2 on a single-layer…