Ammonium and nitrate in ice accretions and snow at two Central European montane locations: δN and δ [Formula: see text] isotope ratios, fluxes and sources.

In many countries worldwide, NO emissions currently decrease as a result of pollution control, while NH emissions stagnate or continue to increase. Little is known about horizontal deposition of NO and NH, the oxidation/neutralization products of these primary pollutants. To close the knowledge gap, we studied atmospheric inputs of NO and NH at two mountain-top sites near the Czech-German-Polish borders during winter.

Nucleation on a stepped surface with an Ehrlich-Schwöbel barrier.

During deposition on a stepped surface the growth mode depends on the conditions such as temperature T, deposition rate F and width of the terraces w. In this work we studied the influence of all the above mentioned characteristics using the kinetic Monte Carlo (kMC) technique. We concentrated on the conditions on the terrace at the moment of the first nucleation.

Stability, interaction and influence of domain boundaries in Ge/Si(111)-5 × 5.

We present a theoretical investigation of the influence of domain boundaries on the Ge/Si(111)-5 × 5 phase using both large-scale DFT simulations and an analytical model. It is shown that different boundary types modify the atomic and electronic structure of the adjoining 5 × 5 domains in very different ways. A simple theoretical model, that describes the energy interaction J between the boundaries and the 5 × 5 phase, is presented and the interaction energy decay J(x) ≈ x(-n) for different domain boundaries is estimated.

Surface nucleation and growth in the system of interacting particles.

Recent experiments on epitaxial growth of metals on graphene have shown a strong dependence of island densities on coverage. These investigations cannot be explained by the standard mean-field nucleation theories. To understand them, we extend to higher coverage the former theory of rate equations developed for the initial state of nucleation, in a system where adsorbate interaction is included.

2D nucleation limited by slow diffusion.

We extend a standard theory of second-layer nucleation in the regime of low temperature, where the diffusion is the limiting process. The theory takes into consideration the fluctuations of the adatoms and the distribution of stable clusters on a surface, and yields an expression for the nucleation rate and time evolution of the density of stable clusters. When diffusion is slow, the fluctuations of the monomer distribution play an important role and results differ qualitatively and quantitatively from those obtained using the standard rate-equation approach to nucleation.