Quantum mechanical and reaction dynamics investigation of butyl acetate synthesis in the presence of pyridinium hydrogen sulfate

Energy Applications of Ionic Liquids: Recent Developments and Future Prospects

Ionic liquids (ILs) consisting entirely of ions exhibit many fascinating and tunable properties, making them promising functional materials for a large number of energy-related applications. For example, ILs have been employed as electrolytes for electrochemical energy storage and conversion, as heat transfer fluids and phase-change materials for thermal energy transfer and storage, as solvents and/or catalysts for CO2 capture, CO2 conversion, biomass treatment and biofuel extraction, and as high-energy propellants for aerospace applications. This paper provides an extensive overview on the various energy applications of ILs and offers some thinking and viewpoints on the current challenges and emerging opportunities in each area. The basic fundamentals (structures and properties) of ILs are first introduced. Then, motivations and successful applications of ILs in the energy field are concisely outlined. Later, a detailed review of recent representative works in each area is provided. For each application, the role of ILs and their associated benefits are elaborated. Research trends and insights into the selection of ILs to achieve improved performance are analyzed as well. Challenges and future opportunities are pointed out before the paper is concluded.

A combined DFT and FT-IR study on the surface interactions in alumina supported ionic liquid [H-Pyr]+[HSO4]. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020;226:117545. [PMID: 31710889 DOI: 10.1016/j.saa.2019.117545]

The surface interactions in [H-Pyr]⁺[HSO₄]^-/γ-Al₂O₃ system (prepared by wetness impregnation method) are investigated theoretically and experimentally. For that purpose, atoms in molecules theory, natural bond orbital and natural charge population analyses in a combination with a vibrational spectroscopy (FT-IR) are used. It is established that a bond formation between the hydrogen sulfate anion and the alumina influences the IL-support interaction in a great extent. However, a support-cation and a cation-anion interaction in the immobilized [H-Pyr]⁺[HSO₄]^- present as well. A comparative analysis between the experimental and the calculated vibrational modes is carried out and a significant number of infrared bands are assigned. The results indicate a good correlation between the experimental and the theoretical IR frequencies. It is found that the aforementioned interactions affected the vibrational frequencies in the supported IL.

Crystal structure and DFT study of a zinc xanthate complex

In the title compound, the Zn^II ion is coordinated by two N atoms of the N,N,N′,N′-tetra­methyl­ethylenedi­amine ligand and two S atoms from two 2-meth­oxy­ethyl xanthate ligands. Two C—H⋯O and two C—H⋯S intra­molecular inter­actions occur. In the crystal, mol­ecules are linked by C—H⋯O and C—H⋯S hydrogen bonds, forming a three-dimensional supra­molecular architecture.

In the title compound, bis­(2-meth­oxy­ethyl xanthato-κS)(N,N,N′,N′-tetra­methyl­ethylenedi­amine-κ²N,N′)zinc(II) acetone hemisolvate, [Zn(C₄H₇O₂S₂)₂(C₆H₁₆N₂)]·0.5C₃H₆O, the Zn^II ion is coordinated by two N atoms of the N,N,N′,N′-tetra­methyl­ethylenedi­amine ligand and two S atoms from two 2-meth­oxy­ethyl xanthate ligands. The amine ligand is disordered over two orientations and was modelled with refined occupancies of 0.538 (6) and 0.462 (6). The mol­ecular structure features two C—H⋯O and two C—H⋯S intra­molecular inter­actions. In the crystal, mol­ecules are linked by weak C—H⋯O and C—H⋯S hydrogen bonds, forming a three-dimensional supra­molecular architecture. The mol­ecular structure was optimized using density functional theory (DFT) at the B3LYP/6–311 G(d,p) level. The smallest HOMO–LUMO energy gap (3.19 eV) indicates the suitability of this crystal for optoelectronic applications. The mol­ecular electrostatic potential (MEP) further identifies the positive, negative and neutral electrostatic potential regions of the mol­ecules. Half a mol­ecule of disordered acetone was removed with the solvent-mask procedure in OLEX2 [Dolomanov et al. (2009 ▸). J. Appl. Cryst.42, 339–341] and this contribition is included in the formula.