The effect of nanosized ceria on supported Cu nanoparticles was investigated at an atomic level and correlated to the catalytic activity on the water–gas shift reaction (WGSR) rate. For Cu/Al2O3, increasing the Cu nanoparticle size leads to a decrease in the oxygen coverage and an increase in the bond length of Cu–O. When different loadings of nanosized ceria are introduced to the Cu/Al2O3 catalysts, no significant change occurred in the Cu particle size, the Cu–Cu bond length, or the oxygen coverage. However, ceria is able to interact with the Cu nanoparticles to increase the Cu–O bond length, and a linear correlation between ceria loading, Cu–O bond length, and WGSR rate was found. Hence, while previous reports claim that ceria leads to Cu nanoparticle stabilization or interface active sites, we have shown that the ceria tailors the Cu–O bond length, which has been shown to be a determinant of the WGSR rate.

In chiral symmetry breaking, populations with initial enantiomeric excess (EE) are probabilistically favored if statistical fluctuation is present, as in nature. Stochastic methods correctly describe chiral symmetry breaking by taking into account the quantitative enantiomeric difference (excess or deficiency) and the statistical fluctuation amplitude, which is inversely proportional to the absolute size of the populations involved. From this, we obtain a law, which indicates that such a favoring probability decreases exponentially [P(EE) = 1/(e + 1)] with an initial enantiomeric deficiency mediated by statistical fluctuation. Obviously, chiral symmetry breaking equally favors populations without enantiomeric excess [P(0) = 1/2]. However, if deterministic methods are considered, chiral symmetry breaking will strictly favor the population with an initial enantiomeric excess (EE). To study these stochastic chiral symmetry breaking processes the autocatalytic Frank model was considered. Summarizing, our results show that the initial enantiomeric excesses are not entirely responsible for the final state configuration of autocatalytic finite systems.

This study consists of the theoretical analysis of some organic molecules and their inorganic similar compounds, through substitution of two carbon atoms by boron and nitrogen atoms. The methods DFT/B3-LYP/TZVPP and CC2/TZVPP were considered. Firstly, ethane, ethene, and ethyne molecules (based on C atoms and their BN/NB analogs) were studied. These molecules were considered as a reference for the analysis of other molecules with functional groups. These molecules with functional groups are: ethanol, ethanal (and its isomer ethenol), ethanoic acid (and its isomer ethenediol), ethylamine, ethylbenzene, propane, and fluoroethane. We studied the energies, bond length, population analysis, and bond order. The dative bonds (BN) are bigger and weaker than that covalent based on C atoms. The dative bond has π character when the BN bond is double and triple. It is possible to distinguish two different behaviors for BN bonds, one when the functional group is bounded to the B atom, and the other to the N atom. When the functional group is bounded to the B atom, the BN bond is weaker and lengthier than that when the same group is bounded to the N atom. However, the isomer with weaker BN bond is the most stable one. Graphical abstract Comparative studies of dative bonds among substituted inorganic molecules, e.g., BN-ethanol, show important differences in terms of length and energy in comparison to organic analogous. There is also a difference when comparing BN or NB molecules (according to witch atom the functional group is bonded to, B or N); bond length, for example, is bigger for BN molecules.

The effects of promoters and additives on the electronic properties and structural properties of Pt catalysts still need to be understood. The present work investigates the effects of the Pt loading and the use of chloride additive on the structural properties of Pt/Al2O3 and its catalytic activity towards the WGS reaction. The presence of Cl affected the morphology and oxygen coverage of the Pt nanoparticles. However, these parameters did not affect the surface electronic properties, due to a compensation effect between the size of the Pt0 core and oxygen coordinated on the shell (NPt‐O). Despite the structural differences, the catalytic activity for the WGS reaction was similar for the chloride‐free sample and the catalyst containing chloride. The effect of the Pt loading was also studied, with the “apparent” catalytic activity per site of Pt (TOF) decreasing with increasing metal loading. Increasing the Pt loading led to an increase of the low‐coordination Pt0 sites at the surface of the NPs, resulting in stronger Pt‐CO integration and consequent poisoning of the active sites.

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