Study of thermodynamic properties of imidazolium-based ionic liquids and investigation of the alkyl chain length effect by molecular dynamics simulation

Structural and dynamic properties of eutectic mixtures based on menthol and fatty acids derived from coconut oil: a MD simulation study

The structural and dynamical properties of the binary mixture of Menthol (MEN) and Fatty acids (FAs) were investigated using molecular dynamics simulations. To this end, the relationship between the structural and dynamical properties of the eutectic mixtures of MEN and FAs with different molar percentages of FAs are studied. Structural properties of the eutectic mixtures were characterized by calculating the combined distribution functions (CDFs), radial distribution functions (RDFs), angular distribution functions (ADFs), hydrogen bonding networks, and spatial distribution functions (SDF). Additionally, our Results indicated robust interactions between menthol and Caprylic acid molecules Finally, the transport properties of the mixtures were investigated using the mean square displacement (MSD) of the centers of mass of the species, self-diffusion coefficients and vector reorientation dynamics (VRD) of bonds. Overall, our simulation results indicated that intermolecular interactions have a significant effect on the dynamic properties of species.

Impact of alkyl chain length and water on the structure and properties of 1-alkyl-3-methylimidazolium chloride ionic liquids

Conformational isomerism in C_nmim Cl (n = 2, 4, 6, 8, and 10) is identified by marker IR bands for the first time.

Comparison of Electronic and Physicochemical Properties between Imidazolium-Based and Pyridinium-Based Ionic Liquids

To compare 1-butyl-3-methylimidazolium ([BMIM]⁺)- and 1-butyl-3-methylpyridinium ([BMPy]⁺)-based ionic liquids (ILs) and investigate the influence of intramolecular and intermolecular interactions on physicochemical properties, a systematic study was performed on the electronic structures and physicochemical properties of [BMIM]⁺ tetrafluoroborate ([BMIM][BF₄]), [BMIM]⁺ hexafluorophosphate ([BMIM][PF₆]), [BMIM]⁺ hydrogen sulfate ([BMIM][HSO₄]), [BMIM]⁺ methylsulfate ([BMIM][MSO₄]), [BMIM]⁺ ethylsulfate ([BMIM][ESO₄]), [BMPy]⁺ tetrafluoroborate ([BMPy][BF₄]), [BMPy]⁺ hexafluorophosphate ([BMPy][PF₆]), [BMPy]⁺ hydrogen sulfate ([BMPy][HSO₄]), [BMPy]⁺ methylsulfate ([BMPy][MSO₄]), and [BMPy]⁺ ethylsulfate ([BMPy][ESO₄]) using density functional theory and molecular dynamics simulation. The results reveal that aggregation behavior exists in [HSO₄]^-- and [ESO₄]^--based ILs, and the differences between their densities and self-diffusion coefficients are smaller when there is an aggregation effect in ILs. A dimer is formed by two strong hydrogen bonds between two [HSO₄]^- anions in [HSO₄]-based ILs, and the existence of hydrogen bonds in ILs increases density and decreases the self-diffusion coefficient. The intermolecular interaction strength of [BMIM]⁺-based ILs is stronger than that of [BMPy]⁺-based ILs.

Nanoscopic Study on Aliphatic Choline-Based Naphthenic Acid Ionic Liquids: Structural and Dynamical Properties

The structural and dynamical properties of two cholinium-based naphthenic acid ionic liquids (CBNAILs), namely, cholinium cyclopentane carboxylate ([CH][CPC]) and cholinium cyclohexane carboxylate ([CH][CHC]) have been studied using the classical molecular dynamics simulations and quantum mechanical methods. The results have also been compared with corresponding aromatic ones. Interaction energies, charge transfers, and hydrogen bondings between the studied ion pairs were investigated by density functional theory calculations and also the theory of atoms in molecules. Density, mean-square displacement, self-diffusivity, viscosity, electrical conductivity, transference number, ionicity, and fragility have been computed for the studied CBNAILs in the temperature range of 298.15-450 K and at 0.1 MPa. The simulated values were in good agreement with experimental data where they exist. The structural features of these CBNAILs were characterized by calculating the partial site-site radial distribution functions and spatial distribution functions. The results show a density cap of hydrogen atoms of hydroxyl groups of cations extended along the COO^- groups of anions. In these ILs, [CPC]^- and [CHC]^- are connected by hydrogen bonding to [CH]⁺ mainly through the carboxylate group. Increasing the number of carbon atoms in the ring of [CHC]^- with respect to [CPC]^- makes remarkable changes in self-diffusions, electrical conductivities, and viscosities. Altogether, this work gives a better insight into the dynamics and structuring of this class of biodegradable ILs at a molecular level.

Multiscale modeling of the trihexyltetradecylphosphonium chloride ionic liquid

Hierarchical trihexyltetradecylphosphonium cationic and chloride anionic models.

Local order and long range correlations in imidazolium halide ionic liquids: a combined molecular dynamics and XAS study

EXAFS spectroscopy and molecular dynamics simulations have been combined to unveil the effect of the cation and anion nature on the local order and long range interactions of imidazolium halide ionic liquids.