Nature of intermolecular interactions in mixed solvents

Density, viscosity and refractive index of the dimethyl sulfoxide + o-xylene system

“…18 A factor that would cause an increase of the V E values (a positive effect) is the breakdown of DMSO self-association and the destruction of molecular order in the aromatic hydrocarbon on mixing, as is reflected by the positive heats of mixing reported in literature for this system. 19 All these above factors play a role in deciding the magnitude of the excess molar volumes; hence the obtained V E values are moderately negative. As the temperature is lowered, the packing effect of the compounds is lowered; therefore V E became less negative, as was observed by Pal and Kumar 20 for mixtures exhibiting a similar behavior.…”

Inhibition of Bubble Coalescence by Electrolytes in Binary Mixtures of Dimethyl Sulfoxide and Propylene Carbonate

“…Note that the physical properties including relative permittivity, density, viscosity, donor numbers, refractive index, and heat capacity of this binary mixture all exhibit monotonic changes with the solvent composition, − implying that the inhibition of bubble coalescence is not strongly influenced by these properties. Also, the investigation of heat of mixing for DMSO and PC indicates that there are no hydrogen bonds in this system and the decisive roles in the intermolecular interactions are those of orientation and induction interactions of the two polar molecules . Accordingly, a possible explanation for the minimum in bubble coalescence is that DMSO and PC form complexes at a certain solvent composition due to the dipolar interactions.…”

“…Also, the investigation of heat of mixing for DMSO and PC indicates that there are no hydrogen bonds in this system and the decisive roles in the intermolecular interactions are those of orientation and induction interactions of the two polar molecules. 17 Accordingly, a possible explanation for the minimum in bubble coalescence is that DMSO and PC form complexes at a certain solvent composition due to the dipolar interactions. Such complexes at the airliquid interface may reduce the film thinning and rupture between bubbles, thereby leading to inhibition of bubble coalescence.…”

“…16 Accordingly, DMSO molecules and PC molecules might form solvent complexes due to the orientation and induction interactions between these two polar molecules. 17 For example, three SdO groups from three DMSO molecules could be interacting with three carbon-oxygen groups from one PC molecule to form one solvent complex; that is, the mixed solvents can exactly form complexes at the PC mole fraction of 25% (this is equivalent to a volume fraction of PC of ∼28%). The outer surface of such a solvent complex consisting of a hydrocarbon shell may exhibit slight solvophobic properties.…”

“…On the other hand, the negative center and positive center are, respectively, located on the oxygen atom and sulfur atom for the DMSO molecule. , In addition, the intermolecular interactions in DMSO/PC mixtures are mainly dependent on the interactions between the SO group of DMSO and the CO (or C−O) group of PC . Accordingly, DMSO molecules and PC molecules might form solvent complexes due to the orientation and induction interactions between these two polar molecules . For example, three SO groups from three DMSO molecules could be interacting with three carbon-oxygen groups from one PC molecule to form one solvent complex; that is, the mixed solvents can exactly form complexes at the PC mole fraction of 25% (this is equivalent to a volume fraction of PC of ∼28%).…”