In the present work, the chemical reactivity of indaziflam N-[(1R,2S)-2,3-dihydro-2,6-dimethyl-1H-inden-1 yl]-6-[(1R)-1-16 fluoroethyl]-1,3,5-triazine-2,4-diamine so called indaziflam (IND) and its metabolites: triazine indanone (ITI), indaziflam carboxylic acid (ICA) and fluoroethyldiaminotriazine (FDAT) was analyzed. The calculations were performed at the X/6 311++G(2d,2p) (where X=B3LYP, M06, M06L and wB97XD) level of theory, in the aqueous phase. The results indicate that ITI is the more reactive followed by ICA, IND and FDAT. The distribution of the active sites was determined evaluating the Fukui function employing the frozen core and finite difference approximations. For electrophilic attacks, IND shows the more reactive zone on the benzene ring, ITI and ICA on the nitrogen atom in the central section and FDAT on its nitrogen atoms. The more nucleophilic sites for IND are observed on the carbon atoms of triazine, on the carbonyl group for ITI, on the carboxylic group for ICA, and on the nitrogen atoms of triazine for FDAT. For free radical attacks case, the more reactive sites for IND are on the benzene and triazine rings, on the carbonyl group, nitrogen of the central section, and nitrogen atoms of triazine, for ITI, carboxylic group for ICA, and on the nitrogen atoms of triazine ring for FDAT.

An electrochemical study of Co electrodeposition onto polycrystalline Pt from an aqueous solution containing 10-2 M CoCl2 + 1 M NH4CI (pH = 9.3) was conducted at overpotential conditions. The current density transients showed two maxima that corresponded to two nucleation and growth processes. The entire transient behavior was adequately predicted considering the contribution to the total current of four different processes: a Langmuir-type adsorption process, a diffusion-controlled two-dimensional instantaneous nucleation, and two three-dimensional nucleation and growth processes.

In present work, we analyzed the copper electrodeposition onto GCE (System I) and HOPGE (System II) from perchlorate solutions. The current density transients obtained from system I and II were well described through a kinetic mechanism that involves four different contributions: (a) a Langmuir type adsorption process, b) an electron transfer from Cu2+→Cu+, (c) a 3D nucleation limited by a mass transfer reaction and (d) a proton reduction process. It was observed that the values of the nucleation rate, the number of active nucleation sites were increased with the overpotential and they are bigger onto GCE in comparison with HOPGE.

In the present work we calculated reactivity descriptors for atrazine at MP2/6-311++G(2d,2p)//B3LYP/6-311++G(2d,2p) level in order to analyze its reactivity. Reactivity descriptors such as ioniza-tion energy, molecular hardness, electrophilicity, condensed Fukui function and total energies were determined to identify changes in the reactivity of atrazine in the gas and aqueous phases. The influence of the solvent was taken into account with the PCM model. The values of the reactivity descriptors indicated that the interaction of atrazine with water diminished its reactivity in comparison with the exhibited in gas phase. Also, it was found that the electrophilic and free radical attacks were equivalent and they were located on all the cases in the ethylamine and isopropylamine groups.

En el presente trabajo calculamos descriptores de reactividad para la atrazina, en el nivel de teoría MP2/6-311++G(2d,2p)//B3LYP/6-311++G(2d,2p), con la intención de analizar su reactividad. Se calcularon descriptores tales como energía de ionización, dureza, electrofilicidad, funciones de Fukui y diferencias de energías para identificar los cambios de reactividad de la atrazina en fase gas y en fase acuosa. La influencia del disolvente se tomó en cuenta empleando el modelo PCM. Los descriptores de reactividad calculados sugieren que en agua la reactividad de la atrazina disminuye en comparación con la atrazina en fase gas. Se encontró que las reactividades, electrofilica y por radicales libres, en la atrazina son equivalentes y localizadas en todos los casos en los grupos etilenamina e isopropilamina.

We carried out an electrochemical study about zinc electrodeposition onto GCE and HOPG substrates from an electrolytic plating bath containing 0.01M ZnSO4 + 1M (NH4)2SO4 at pH 7. Under our experimental conditions the predominant chemical species was the complex [ZnSO4(H2O)5]. The chronoamperometric study showed that zinc electrodeposition follows a typical 3D nucleation mechanism in both substrates. The average dG calculated for the stable nucleus formation was 6.92 x 10-21 J nuclei"1 and 1.35 x 10-20 J nuclei"1 for GCE and HOPG, respectively. The scanning electron microscopy (SEM) images showed different nucleation and growth processes on GCE and HOPG substrates at same overpotential.

It was carried out an electrochemical study of the cobalt electrodeposition onto HOPG electrode from an aqueous solution containing 10-2 M of CoSO4 + 1M (NH4)2SO4. Nucleation parameters such as nucleation rate, density of active nucleation sites, saturation nucleus and the rate constant of the proton reduction reaction (kPR) were determined from potentiostatic studies. An increase in kPR values with the decrease in the applied potential suggested a competition between H+ and Co2+ by the active sites on the surface. The ΔG energy calculated for the formation of stable nucleus was 8.21x10-21 J/nuclei. The AFM study indicated the formation of small clusters of 50-400 nm in diameter and 2-120 nm in height.

An electrochemical study of zinc deposition was carried out in baths containing 0.5 M ZnCl2 and 0.4 M H3BO3. From the voltammetric study it was found that, in our experimental conditions, zinc electrodeposition is quasi-reversible and occurs under charge transfer control. The average coefficient diffusion calculated was D = 7.14 × 10-6 cm²s-1 while the standard constant at electrode charge was 8.78 × 10-3 cms-1. The nucleation and growth parameters determined from the potentiostatic study showed that, at bigger overpotentials, a vertical growth is favored, suggesting a dendritic growth. The critical cluster's size calculated was 2, indicating that each active site is formed by two zinc atoms on the glassy carbon electrode (GCE) surface, while the ΔG for the formation of stable nucleus was 1.35 × 10-20 J/nuclei. The Scanning Electron Microscopy images showed thin platelets of hexagonal crystals and dendrites at lower and higher overpotentials applied, respectively.

Se realizó un estudio electroquímico del proceso de deposito de zinc a partir de baños que contienen 0.5 M ZnCl2 y 0.4 M H3BO3. Del estudio voltamperométrico se encontró que, en nuestras condiciones experimentales, la electrodepositación del zinc es cuasi reversible y ocurre bajo un control por transferencia de carga. El coeficiente de difusión calculado fue D = 7.14 × 10-6 cm²s-1 mientras que la constante de velocidad estándar del electrodo fue 8.78 × 10-3 cms-1. Los parámetros de nucleación y crecimiento obtenidos a partir del estudio potenciostático; mostraron que a grandes sobrepotenciales la velocidad de crecimiento perpendicular se favorece, sugiriendo un crecimiento dendrítico. El tamaño crítico de núcleo calculado fue de 2, indicando que cada sitio activo está formado por dos átomos de zinc en la superficie del electrodo de carbón vitreo (GCE). La ΔG requerida para formar un núcleo estable fue de 1.35 × 10-20 J/núcleo. Las imágenes obtenidas por medio de microscopia electrónica de barrido mostraron cristales hexagonales planos y dendritas a bajos y altos sobrepotenciales, respectivamente.

We carried out an electrochemical study of the cobalt electrodeposition onto glassy carbon electrode from an aqueous solution containing 10-2 M of CoSO4 + 1 M (NH4)2SO4 at natural pH 4.5. The potentiostatic study indicated a progressive 3D nucleation and growth during the deposition process. The average diffusion coefficient calculated for this system was 2.65 X 10-6 cm² s-1 while the ΔG for the formation of stable nucleus was 6.50 X 10-20 J/nuclei. The scanning electron microscopy images indicated the formation of small and homogeneous nucleus onto GCE of approximately 300 nm.

A theoretical quantum study on the distribution of electrophilic and nucleophilic active sites on silver surfaces with (100) orientation and modeled as finite clusters is reported. From Hartree-Fock and Density Functional Theory calculations with the LANL1MB and LANL2DZ basis set, we found that the electrophilic active sites are extended and they are formed by a group of atoms. The nucleophilic active sites were located on hollow positions. The numbers of electrophilic and nucleophilic active sites were 1.86X10(14) and 5.98X10(14) active sites cm-2 respectively.

Se reporta un estudio teórico cuántico de la distribución de sitios activos electrofílicos y nucleofílicos sobre superficies de plata con orientación (100) modeladas con cúmulos de tamaño finito. A partir de cálculos Hartree-Fock y de la Teoría de los Funcionales de la Densidad con las bases LANL1MB y LANL2DZ encontramos que los sitios electrofílicos son extendidos y formados por un grupo de átomos. Los sitios nucleofílicos se localizaron en posiciones en el hueco. El número de sitios electrofílicos y nucleofílicos fueron 1.86X10(14) y 5.98X10(14) sitios-activoscm-2 respectivamente.