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Information × Registration Number 0224U031873, 0123U102729 , R & D reports Title Phase behaviour of ionic liquids in a disordered confinement popup.stage_title Head Patsahan Oksana V., Доктор фізико-математичних наук Registration Date 27-06-2024 Organization Institute of Condensed Matter Physics of the National Academy of Sciences of Ukraine popup.description2 The aim of the research work is to develop a theory of phase transitions in ionic liquids with complex structures of molecular ions under conditions of disordered spatial confinement formed by a matrix of a immobile particles of porous material. To achieve this, during this stage, a theoretical approach is developed to describe the thermodynamic properties of an ionic liquid in a disordered porous medium with molecular cations represented by charged rigid spherocylinders with a charge located at one end of the spherocylinder. The approach combines the generalization of scaled particle theory and the associative mean spherical approximation. For the “ionic liquid-matrix” system, analytical expressions for the free energy, pressure, and chemical potentials are obtained, which include contributions from the reference system represented as a two-component mixture of hard spherocylinders and hard spheres confined in a matrix of disordered uncharged hard spheres, as well as contributions from the ionic subsystem represented as a mixture of free ions and ion pairs being in chemical equilibrium according to the mass action law. An explicit form of the system of nonlinear equations is derived to determine the degree of ion dissociation and Blum’s screening parameter. Using the Monte Carlo method, a series of computer simulations are carried out on an equimolar mixture of positively charged hard spherocylindrical particles (cations) and negatively charged spheres in both bulk and matrices of different porosity. Radial distribution functions and binding degrees between cations and anions are calculated at different densities and temperatures. Comparisons are made with theoretical results and similar systems where cations are flexible and rigid chains of equivalent length. It was shown that the critical temperature and critical density in the systems with spherocylindrical cations decrease with reduced matrix porosity and are lower than those in the systems with chain cations. Product Description popup.authors Hvozd Taras V. Holovko Myroslav F. Kalyuzhnyi Yurii V. Kukarkin Nazar B. Patsahan Taras M. popup.nrat_date 2024-06-27 Close