Publications by authors named "Roberto Macchieraldo"

To gain a deeper understanding of the TiCl4 solvation effects in multi-component ionic liquids, we performed ab initio molecular dynamics simulations of 1-butyl-3-methylimidazolium [C4C1Im]+, tetrafluoroborate [BF4]-, chloride [Cl]- both with and without water and titanium tetrachloride TiCl4. Complex interactions between cations and anions are observed in all investigated systems. By further addition of water and TiCl4 this complex interaction network is extended.

View Article and Find Full Text PDF

By means of classical molecular dynamics simulation the interfacial properties of methanol and n-dodecane, which are two potential candidate solvents for use in non-aqueous liquid-liquid extraction, were assessed. The question of how the interface changes depending on the concentration of extractant (tri-n-butyl phosphate) and salt (LiCl) is addressed. Two different models to represent systems were used to evaluate how LiCl and tri-n-butyl phosphate affect mutual miscibility, and how the last-named behaves depending on the chemical environment.

View Article and Find Full Text PDF

With the aid of ab initio molecular dynamics simulations, we investigate an ionic liquid (IL) mixture composed of three components 1-butyl-3-methylimidazolium [CCIm], tetrafluoroborate [BF], and chloride [Cl] without and with water. In the pure IL mixture, we observe an already complex network of interactions between cations and anions, and addition of water to the system even extends the complexity. Observed number integrals show that the coordination number between cations and anions is reduced in the system with water compared to that in the pure system.

View Article and Find Full Text PDF

In this work, we assess the fundamental aspects of mutual miscibility of solvents by studying the mixing of two potential candidates, methanol and n-dodecane, for nonaqueous solvent extraction. To do so, H NMR spectroscopy and molecular dynamics simulations are used jointly. The NMR spectra show that good phase separation can be obtained by adding LiCl and that the addition of a popular extractant (tri- n-butyl phosphate) yields the opposite effect.

View Article and Find Full Text PDF

The electroorganic C,C coupling of phenols to other aryl components is controlled by the fluoroalcohol-alcohol mixture solvents. Classical molecular dynamics and static density functional theory reveal that both kinds of solvents interact with the substrates, influencing the electronic structure of a phenoxyl radical intermediate in a cooperative manner to achieve maximal efficiency and selectivity. Simulations of the electrolyte-electrode interface showed that the substrates adsorb on the diamond surface in such a way that the repulsive fluorous-lipophilic interactions can be minimized and the attractive lipophilic-lipophilic interplay can be maximized, whereas the advantageous hydrogen bonding with the solvent can be retained.

View Article and Find Full Text PDF

Solvation processes, transport properties, and fluidity of condensed phases can be described considering the void space between the particles of the system. In this work a novel algorithm for the analysis of this void in molecular dynamics simulations is presented. Based on suitable void spheres which are fitted between the atoms a void domain is defined employing a Voronoi tessellation scheme.

View Article and Find Full Text PDF