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Information × Registration Number 0211U009485, 0109U001312 , R & D reports Title Pico- and nanoscaled processes in ionic liguid and ion-molrcular systems as a basis for novrl functional materials popup.stage_title Head V'unik Ivan Nikolaiovich, Registration Date 23-12-2011 Organization Kharkov National University named after V.N. Karazin popup.description2 Objects of investigation: carbon nanotubes (CNT); electrolyte solutions inside the carbon nanotubes; nickel chloride solutions in methanol; solutions of tetraalkyl ammonium salts in acetonitrile; imidazolium ionic liquids. The aim of this work is to obtain detailed and reliable information on the microscopic structure, ionic and molecular dynamics on pico- and nano- scales, and also on interparticle interactions in nonaqueous ion-molecular systems and ionic liquids. Methods of investigation: ab initio and classic molecular dynamics simulation, conductometry, NMR spectroscopy. Electric conductivities of Bu4NBr and Et4NBF4 acetonitrile solutions with concentrations 1·10-4 - 1 mol/dm3 were determined at temperatures 5-55°С. From NMR experimental data the existence of penetrating ionic pairs in concentrated solutions was suggested. Quasilattice model with conjunction with ionic association is proven to be adequate for predicting of conductence of solutions with moderate concentrations. The usage of the free energy functional within plain wave pseudopotential density functional theory framework were adopted for calculation of electronic properties of CNT. Electronic structure of CNTs with topologies armchair and zigzag was calculated. 1H, 2H and 13C NMR spectra have been used to test the Ni2+ solvation shell composition in methanol solution of NiCl2. Using 2H NMR allowed us to detect for the first time OD-signal of methanol in the primary solvation shell of Ni2+ cation. The new phenomenological account for electronic polarization and charge transfer within classical nonpolarizable FF is proposed. Based on the results of our ab initio molecular dynamics calculations using explicit ionic environment, we modified the electrostatic interaction potential of 1-ethyl-3-methylimidazolium and 1-buthyl-3-methylimidazolium tetrafluoroborates. The temperature dependencies of transport properties of ionic liquids are well predicted by proposed force-fields. As it follows from the results of the performed molecular dynamics simulations on liquid МеОН, AN and DMSO confined by single-walled carbon nanotubes the translational diffusion coefficient changes continuously with decreasing CNT diameter. Dynamical properties of electrolyte solutions inside CNT are influenced by two factors: the geometry of confinement and the structure of ionic subsystem in solution. On the base of self-diffusion coefficients of Et4N+ and BF4- inside the CNT considerable decrease carbon nanomaterials with effective diameters of up to 3 nm are suggested as an electrode material for modern electrochemical double-layer supercapacitors. Based on the re-orientational dynamics of liquid DMSO in confinements analysis, it was shown that cryoprotective properties of DMSO are stipulated by the considerable growth of microscopic relaxation times in the presence of spatial confinements. Product Description popup.authors Агєєнко В. В'юник І. Калугін О. Колесник Я. Корсун О. Кулік Р. Лукінова О. Марєха Б. Чабан В. Черножук Т. popup.nrat_date 2020-04-02 Close