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Ab initio molecular dynamics simulations were performed in order to study chemisorption, electronic properties, and desorption of glycine at wet pyrite surfaces focusing on the role of surface point defects. Results showed that the formation of such point defects has an appreciable impact on the electronic structure and reactivity of this surface.

Using density functional theory study was conducted on the interaction of alkanethiolates with small coinage metal clusters of copper and gold. The relativistic origin of differences between Cu and Au is discussed, and an analysis ob bonding considerations is presented.

Car-Parrinello molecular dynamics are used to study the mechanism of specific acid-catalyzed glycosidic bond formation between methanol and alpha-D-glucopyranoside in aqueous solution at 300 K. The reaction proceeded through a non-solvent equilibrated oxacarbenium cation intermediate characterized by the loss of a hydrogen-bonding interaction between the ring oxygen and solvating water.

The analysis on the role played by aliphatic polymer chains in the transduction of external forces to mechanophores being at the heart of force spectroscopy and sonication experiments is presented. The studies have highlighted the necessity of considering the polymer chains explicitly when thinking about mechanochemical manipulation and have also announced the possibility of tuning the properties of mechanoresponsive polymers by tailoring the force-transducing chain molecules.

Ab initio molecular dynamics are used for examining the mechanisms and free energetics underlying the formation of peptides from [alpha]-amino acids and [alpha]-amino acid N-carboxyanhydrides (NCAs) in bulk water at both ambient and extreme temperatures. The results have helped in understanding the affect of elevated temperatures and increased pressures on organic reactions in aqueous solutions and also on peptide bond formation and peptide hydrolysis in aqueous media.

The ab initio molecular dynamics studies are conducted to explain the various mechanisms involved in the activation of amino acids in bulk water in ambient, as well as extreme temperature-pressure thermodynamic conditions. The analysis proves that the formation of such activated species is highly favored by the extreme conditions.

Peptide synthesis is examined in various aqueous environments, which has provided details of free energy profiles and pathways that are at the center of amino acid activation via N-carboxyanhydrides (NCAs) and subsequent elongation. Pyrite surfaces have acted as catalysts, thus leading to remarkable reductions of free energy barriers by scaffolding immobilization of reactants.

Ab initio molecular dynamics (MD) simulations of the amino acid, glycine at the water/pyrite interface, which can be carried out at the Iron-Sulfur World (ISW) is used for understanding the pyrite assisted peptide bond formation, which is the adsorption of GLY on the pyrite surface and its possible activation. It is seen that the GLY easily desorbs from a pyrite/water interface through hydrogen-bond assistance.

The quinizarin chemisorbed on the basal-plane (0001) surface of alpha-Al2O3 is perpendicular on the surface and forms chelate bonds with surface aluminum atoms at exposed sites. This was observed ab initio calculations. The results also shows that the electronic characteristics due to long-range surface effects cannot explain the improved spectral hole-burning properties of chemisorbed quinizarin.

By a combination of electron paramagnetic resonance spectroscopy, finite-temperature ab initio simulations, and electronic structure analyses, the activation of molecular dioxygen at the interface of gold nanoparticles and titania in Au/TiO 2 catalysts is explained at the atomic scale by tracing processes down to the molecular orbital picture. Direct evidence is provided that excess electrons in TiO 2 , for example created by photoexcitation of the semiconductor, migrate to the gold particles and from there to oxygen molecules adsorbed at gold/titania perimeter sites. Superoxide species are formed more efficiently in this way than on the bare TiO 2 surface. This catalytic effect of the gold nanoparticles is attributed to a weakening of the internal O-O bond, leading to a preferential splitting of the molecule at shorter bond lengths together with a 70% decrease of the dissociation free energy barrier compared to the non-catalyzed case on bare TiO 2 . The findings are an important step forward in the clarification of the role of gold in (photo)catalytic processes.