ARTICLE This journal isMetoprolol (MET) belongs to a group of frequently used β 1 -blockers, which often occur in waste waters. The objective of this work was to employ liquid chromatography (LC) and total organic carbon methods to study the photocatalytic degradation of MET in UV irradiated aqueous suspensions of TiO 2 (Wackherr's "Oxyde de titane standard" and Degussa P25), in the presence of different electron acceptors such as molecular oxygen, hydrogen peroxide, potassium bromate, and ammonium persulfate. The degradation rates were found to be strongly influenced by the kind of electron acceptor and the type of catalyst. The optimal amount of hydrogen peroxide and potassium bromate was investigated as well. MET photocatalytic degradation was fastest in the presence of O 2 and potassium bromate with TiO 2 Degussa P25, while mineralization was most efficient in the presence of molecular oxygen alone. In all investigated cases, degradation followed a pseudo-first order kinetics. Reaction intermediates of MET degradation in the presence of different electron acceptors with both catalysts were studied in detail and a number of them were indentified using LC-ESI-MS/MS. The interactions with MET of reactive radical species relevant to this study ( − • 2 O , • OH, • 2 BrO , and − • 4 SO ) were theoretically investigated by means of density functional theory (DFT) computations. § Electronic supplementary information (ESI) available: Influence of electron acceptors on the kinetics of metoprolol photocatalytic degradation in TiO2 suspension. A combined experimental and theoretical study.− 2 8 2 O S , and − 3BrO , can act as electron acceptors to enhance the photodegradation efficiency. These electron acceptors can have several effects including: (I) avoidance of e − −h + recombination because of scavenging of conduction-band electrons; (II) increase of the concentration of • OH and (III) production of other oxidizing species that can enhance the oxidation rate of the substrate and of its intermediate compounds. 10

Density functional theory calculations were used in the theoretical investigation of the adsorption properties of sumanene towards molecules considered as common air pollutants: CO, CO₂ and NH₃. The insignificant perturbation of sumanene after adsorption and the adsorption energies obtained indicate a physisorption mechanism. It was shown that, contrary to carbon nanotubes, sumanene is able to adsorb CO molecules, and that adsorption of CO₂ by sumanene is stronger than adsorption of CO₂ by C₆₀. To better understand the adsorption characteristics of sumanene, density of states and natural bond order analyses were performed, which showed that chemical interactions exist and that these are more important mostly on the convex side. Better adsorption properties were obtained for the concave side as adsorption is dictated by physisorption mechanisms due to the specific bowl-shaped geometry of sumanene, because of which more negative charge is located precisely on the concave side. Molecular electrostatic potential surfaces were also used in order to better locate the adsorption sites and gain additional details about adsorption.

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The aim of this study is to investigate the active components of representative drugs for blood pressure regulation by applying quantum mechanical computer codes and comparison of the same for the sake of obtaining knowledge about the properties associated with the electronic structure of given molecules. The study included three well-known, but not theoretically investigated enough, active components of β-blockers: acebutolol, metoprolol and atenolol. The results are in agreement with the experimental data and were used for initial assumptions concerning the degradation of these compounds.

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We investigated the effects of substitution on the sumanene benzylic CH2 groups with BH and NH groups using density functional theory computations. Our study shows that various properties of sumanene could be finely tuned for the application in the areas closely related to the materials science. Structural properties are significantly altered with such modifications and other properties as well. Charge distributions were evaluated through natural population analysis (NPA), while stability of investigated structures was investigated using quantum molecular descriptors. Using molecular orbital analysis further insight into the effects of substitution was obtained. Potential of sumanene as a candidate for application in the field of organic electronics is assessed through calculations of exciton binding energy. Non-linear optical properties of investigated structures were investigated using the first hyperpolarizability tensor. Special attention was paid to the aromaticity of sumanene. This property was evaluated employing NICS parameter while for detailed study of obtained results we used NBO and NBOdel analysis.

In the context of the macroscopic quantum phenomena of the second kind, we hereby seek for a solution-in-principle of the long standing problem of the polymer folding, which was considered by Levinthal as (semi)classically intractable. To illuminate it, we applied quantum-chemical and quantum decoherence approaches to conformational transitions. Our analyses imply the existence of novel macroscopic quantum biomolecular phenomena, with biomolecular chain folding in an open environment considered as a subtle interplay between energy and conformation eigenstates of this biomolecule, governed by quantum-chemical and quantum decoherence laws. On the other hand, within an open biological cell, a system of all identical (noninteracting and dynamically noncoupled) biomolecular proteins might be considered as corresponding spatial quantum ensemble of these identical biomolecular processors, providing spatially distributed quantum solution to a single corresponding biomolecular chain folding, whose density of conformational states might be represented as Hopfield-like quantum-holographic associative neural network too (providing an equivalent global quantum-informational alternative to standard molecular-biology local biochemical approach in biomolecules and cells and higher hierarchical levels of organism, as well).

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