Titanium(IV) isopropoxide (TTIP) is an important precursor for the production of nanoparticles by spray flame processes. In these processes, the precursor is provided in a solution in a combustible solvent, which is p-xylene here. As no thermophysical data for solutions of TTIP in p-xylene were available in the literature, they were measured in the present work. The vapor-liquid equilibrium was measured at pressures ranging from 20 to 80 kPa. The specific density, viscosity, thermal conductivity, molar isobaric heat capacity, and self-diffusion coefficients were determined experimentally at 101.3 kPa at temperatures between 293.15 and 373.15 K. Sample compositions cover the range from pure TTIP to pure p-xylene. Chemical reactions in the studied system were considered. The experiments were carried out in a way that they do not compromise the results for the thermophysical properties. The vapor-liquid equilibrium data were correlated using the NRTL model. Empirical correlations were established for the other properties. The results provide a rational basis for spray flame process design.

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We present the latest developments in thermodynamic modeling using the SAFT-γ Mie group-contribution equation of state. The group database is updated, featuring now 58 groups; this expanded database incorporates new parameters for interactions between both like and unlike groups. This provides the capability to treat mixtures including alcohols, ethers, ketones, carboxylic acids, and acetates, amines, aromatic and cyclic compounds, electrolytes, inorganic acids, and some common solvents, such as water and acetone. A discussion is provided relating to the assignment of the groups, including some secondary groups that are introduced for multifunctional molecules to capture the influence of molecular polarization effects on the thermodynamic properties. Performance of the SAFT-γ Mie approach is illustrated for a wide variety of systems, highlighting its use in describing solid−liquid as well as vapor−liquid and liquid−liquid equilibria.

A new version release (4.0) of the molecular simulation tool ms2 (Deublein et al., 2011; is presented. Version 4.0 of ms2 features two additional potential functions to address the repulsive and dispersive interactions in a more versatile way, i.e. the Mie potential and the Tang-Toennies potential. This version further introduces Kirkwood-Buff integrals based on radial distribution functions, which allow the sampling of the thermodynamic factor of mixtures with up to four components, orientational distribution functions to elucidate mutual configurations of neighboring molecules, thermal diffusion coefficients of binary mixtures for heat, mass as well as coupled heat and mass transport, Einstein relations to sample transport properties with an alternative to the Green-Kubo formalism, dielectric constant of non-polarizable fluid models, vapor-liquid equilibria relying on the second virial coefficient and cluster criteria to identify nucleation.

The quality of nanoparticles that are obtained by spray flame synthesis depends strongly on the thermophysical properties of the precursor solutions. Solutions of iron­(III) nitrate-nonahydrate (INN) in ethanol are interesting precursor solutions for the production of iron oxide nanoparticles in these processes. However, no data on the thermophysical properties of solutions of INN in ethanol are available in the literature. Therefore, in the present work, the specific density, viscosity, thermal conductivity, and molar isobaric heat capacity of solutions of INN in solvent mixtures of ethanol and water were measured at 101.3 kPa between 288.15 and 333.15 K, solvent compositions ranging from pure ethanol to pure water, and INN molalities up to 1.3 mol kg–1. Empirical correlations of the experimental data are provided.

A method for determining the activity of the solvent in electrolyte solutions by molecular dynamics simulations is presented. The electrolyte solution is simulated in contact with the pure solvent. Between the two phases, there is a virtual membrane, which is permeable only for the solvent. In the simulation, this is realized by an external field which acts only on the solutes and confines them to a part of the simulation volume. The osmotic pressure, i.e., the pressure difference between both phases, is obtained with high accuracy from the force on the membrane, so that reliable data on the solvent activity can be determined. The acronym of the new method is therefore OPAS (osmotic pressure for activity of solvents). The OPAS method is verified using tests of varying complexity. This includes a comparison of results from the OPAS method for aqueous NaCl solutions to results from the literature which were obtained with other molecular simulation methods. Favorable agreement is observed not only for the solvent activity but also for the activity coefficient of NaCl, which is obtained by application of the Gibbs-Duhem equation.

A new version release (4.0) of the molecular simulation tool ms2 (Deublein et al., 2011; is presented. Version 4.0 of ms2 features two additional potential functions to address the repulsive and dispersive interactions in a more versatile way, i.e. the Mie potential and the Tang-Toennies potential. This version further introduces Kirkwood-Buff integrals based on radial distribution functions, which allow the sampling of the thermodynamic factor of mixtures with up to four components, orientational distribution functions to elucidate mutual configurations of neighboring molecules, thermal diffusion coefficients of binary mixtures for heat, mass as well as coupled heat and mass transport, Einstein relations to sample transport properties with an alternative to the Green-Kubo formalism, dielectric constant of non-polarizable fluid models, vapor-liquid equilibria relying on the second virial coefficient and cluster criteria to identify nucleation.

The relative permittivity of dipolar fluids is important in many industrial and scientific applications, e.g. whenever electrolytes or electromagnetic fields are present. For non-polarizable model molecules, it is directly linked to the mutual molecular orientation and thereby usually not accessible by equations of state. However, the recently developed Co-Oriented Fluid Functional Equation for Electrostatic interactions (COFFEE) allows for calculating the orientation