Exploring the Microscopic Aspects of 1-Methyl-3-octylimidazolium Tetrafluoroborate Mixtures with Formamide, -Methylformamide, and ,-Dimethylformamide by Multiple Spectroscopic Techniques and Computations.

The microscopic aspects of 1-methyl-3-octylimidazolium tetrafluoroborate ([MOIm][BF]) mixtures with formamide (FA), -methylformamide (NMF), and ,-dimethylformamide (DMF) were investigated using spectroscopic techniques of femtosecond Raman-induced Kerr effect spectroscopy (fs-RIKES), FT-IR, and NMR. Molecular dynamics simulations and quantum chemistry calculations were also performed. According to fs-RIKES, the first moment of the low-frequency spectrum bands mainly originating from the intermolecular vibrations in the [MOIm][BF]/FA and [MOIm][BF]/DMF systems changed gradually with the molecular liquid mole fraction but that in the [MOIm][BF]/NMF system was constant up to = 0.

Effects of self-hydrogen bonding among formamide molecules on the UCST-type liquid-liquid phase separation of binary solutions with imidazolium-based ionic liquid, [Cmim][TFSI], studied by NMR, IR, MD simulations, and SANS.

The upper critical solution temperature (UCST)-type liquid-liquid phase separation of imidazolium-based ionic liquids (ILs), 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([Cmim][TFSI], where represents the alkyl chain length of the cation, = 6, 8, 10, and 12) binary solutions with formamide (FA) was examined as a function of temperature and the FA mole fraction . The two-phase region (immiscible region) of the solutions is much larger and expands more with the increase in , in comparison with the previous [Cmim][TFSI]-1,4-dioxane (1,4-DIO) systems. An array of spectroscopic techniques, including H and C NMR and IR combined with molecular dynamics (MD) simulations, was conducted on the present binary systems to clarify the microscopic interactions that contribute to the phase-separation mechanism.

Anion Effects on the Mixing States of 1-Methyl-3-octylimidazolium Tetrafluoroborate and Bis(trifluoromethylsulfonyl)amide with Methanol, Acetonitrile, and Dimethyl Sulfoxide on the Meso- and Microscopic Scales.

The mixing states of two imidazolium-based ionic liquids (ILs) with different anions, 1-methyl-3-octylimidazolium tetrafluoroborate (CmimBF) and bis(trifluoromethylsulfonyl)amide (CmimTFSA), with three molecular liquids (MLs), methanol (MeOH), acetonitrile (AN), and dimethyl sulfoxide (DMSO), have been investigated on both mesoscopic and microscopic scales using small-angle neutron scattering (SANS), infrared (IR), and H and C nuclear magnetic resonance (NMR) spectroscopy. Additionally, molecular dynamics (MD) simulations have been conducted on the six combinations of ILs and MLs to observe the states of their mixtures on the atomic level. The SANS profiles of the IL-ML mixtures suggested that MeOH molecules only form clusters in both CmimBF and CmimTFSA, whereas AN and DMSO were homogeneously mixed with ILs on the SANS scale.

Low-Frequency Spectra of 1-Methyl-3-octylimidazolium Tetrafluoroborate Mixtures with Methanol, Acetonitrile, and Dimethyl Sulfoxide: A Combined Study of Femtosecond Raman-Induced Kerr Effect Spectroscopy and Molecular Dynamics Simulations.

In this study, we examined the low-frequency spectra of 1-methyl-3-octylimidazolium tetrafluoroborate ([MOIm][BF]) mixtures with methanol (MeOH), acetonitrile (MeCN), and dimethyl sulfoxide (DMSO), which were obtained by femtosecond Raman-induced Kerr effect spectroscopy (fs-RIKES) and molecular dynamics (MD) simulations. In addition, we estimated the liquid properties of the mixtures, such as density ρ, surface tension γ, viscosity η, and electrical conductivity σ. The line shapes of the low-frequency Kerr spectra of the three [MOIm][BF] mixture systems strongly depend on the mole fraction of the molecular liquid, .

Effects of the long octyl chain on complex formation of nickel(ii) with dimethyl sulfoxide, methanol, and acetonitrile in ionic liquid of [Cmim][TFSA].

In the room-temperature ionic liquid (IL) of 1-methyl-3-octylimidazolium bis(trifluoromethylsulfonyl)amide ([C8mim][TFSA]), the complex formation of Ni2+ with molecular liquids (MLs), dimethyl sulfoxide (DMSO), methanol (MeOH), and acetonitrile (AN), has been examined using ultraviolet (UV)-visible spectroscopy. The overall stability constants log βn, enthalpies , and entropies of the equilibria have been determined to elucidate the mechanism of complex formation. From a comparison of such thermodynamic parameters of the present [C8mim][TFSA] systems with those of the previous systems of 1-ethyl-3-methylimidazolium-based IL, [C2mim][TFSA], the effects of the octyl chain of the imidazolium cation, [C8mim]+, on the complex formation of Ni2+ with MLs have been demonstrated.