Non-equilibrium molecular dynamics of ionic liquids

• Grant number: 17/12063-8
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): April 01, 2018
• Effective date (End): October 01, 2021
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal researcher: Mauro Carlos Costa Ribeiro
• Grantee: Kalil Bernardino
• Home Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 12/13119-3 - Vibrational spectroscopy in condensed phases, AP.TEM
• Associated scholarship(s): 19/04785-9 - Molecular dynamics study of the effect of flexibility over the melting point of ionic liquids, BE.EP.PD

Abstract

Many low temperature molten salts, the so-called ionic liquids, are viscous liquids with complex phase diagrams, as glass transition or crystallization takes place depending on the rate of change of temperature and pressure. In the Laboratório de Espectroscopia Molecular, LEM/IQ-USP, we have been studying Thermodynamics, structure, and dynamics of ionic liquids by calorimetry, X-ray and Raman spectroscopies, and also by computer simulation by equilibrium molecular dynamics. In this research project, we will broaden the computational approach by non-equilibrium molecular dynamics (NEMD). One motivation for NEMD simulations comes from the fact that ionic liquid can be found in mesophases, for which a deep understanding of its nature on the basis of a microscopic view of structure and dynamics is still lacking. NEMD simulations of the systems under different shearing rates will allow for a molecular basis of the rheology of ionic liquids. Furthermore, a promising application of ionic liquids is their usage as lubricants, so that within the context of tribology it is demanding the knowledge of structural and dynamics properties of the fluid under different situations such as under load on the surfaces in relative motion. In this project we will calculate viscosity of ionic liquids under shearing and load in order to relate the apparent viscosity to the structural changes resulting from the non-equilibrium condition. The computer simulations will be also used for the direct calculation of the time correlation function of structural relaxation of ionic liquids in non-equilibrium condition. Models commonly used in computer simulations of ionic liquids, i.e. based on a pair-wise potential energy function, give high viscosity, low ionic diffusion and conductivity of the simulated system in comparison to experimental data. Thus, in the project we will also perform NEMD simulations with polarizable models in order to assess the polarization effects on the viscoelasticity of ionic liquids.

Scientific publications

(8)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BERNARDINO, KALIL; RIBEIRO, MAURO C. C. Relating the structure and dynamics of ionic liquids under shear by means of reverse non-equilibrium molecular dynamics simulations. Physical Chemistry Chemical Physics, v. 23, n. 25 JUN 2021. Web of Science Citations: 0.

LU, JUN; XUE, YAO; BERNARDINO, KALIL; ZHANG, NING-NING; GOMES, WEVERSON R.; RAMESAR, NAOMI S.; LIU, SHUHAN; HU, ZHENG; SUN, TIANMENG; DE MOURA, ANDRE FARIAS; KOTOV, NICHOLAS A.; LIU, KUN. Enhanced optical asymmetry in supramolecular chiroplasmonic assemblies with long-range order. Science, v. 371, n. 6536, p. 1368+, MAR 26 2021. Web of Science Citations: 1.

BERNARDINO, KALIL; ZHANG, YONG; RIBEIRO, MAURO C. C.; MAGINN, EDWARD J. Effect of alkyl-group flexibility on the melting point of imidazolium-based ionic liquids. Journal of Chemical Physics, v. 153, n. 4 JUL 28 2020. Web of Science Citations: 0.

JIANG, WENFENG; QU, ZHI-BEI; KUMAR, PRASHANT; VECCHIO, DREW; WANG, YUEFEI; MA, YU; BAHNG, JOONG HWAN; BERNARDINO, KALIL; GOMES, WEVERSON R.; COLOMBARI, FELIPPE M.; LOZADA-BLANCO, ASDRUBAL; VEKSLER, MICHAEL; MARINO, EMANUELE; SIMON, ALEX; MURRAY, CHRISTOPHER; MUNIZ, SERGIO RICARDO; DE MOURA, ANDR F.; KOTOV, NICHOLAS A. Emergence of complexity inhierarchically organized chiral particles. Science, v. 368, n. 6491, SI, p. 642+, MAY 8 2020. Web of Science Citations: 0.

BERNARDINO, KALIL; GOLOVIZNINA, KATERYNA; GOMES, MARGARIDA COSTA; PADUA, AGILIO A. H.; RIBEIRO, MAURO C. C. Ion pair free energy surface as a probe of ionic liquid structure. Journal of Chemical Physics, v. 152, n. 1 JAN 7 2020. Web of Science Citations: 0.

BERNARDINO, KALIL; LIMA, THAMIRES A.; RIBEIRO, MAURO C. C. Low-Temperature Phase Transitions of the Ionic Liquid 1-Ethyl-3-methylimidazolium Dicyanamide. Journal of Physical Chemistry B, v. 123, n. 44, p. 9418-9427, NOV 7 2019. Web of Science Citations: 0.

BERNARDINO, KALIL; SWIERGIEL, JOLANTA; JADZYN, JAN; BOUTEILLER, LAURENT; DE MOURA, ANDRE FARIAS. Bulkiness as a design element to increase the rigidity and macrodipole of supramolecular polymers. JOURNAL OF MOLECULAR LIQUIDS, v. 286, JUL 15 2019. Web of Science Citations: 0.

BERNARDINO, KALIL; DE MOURA, ANDRE FARIAS. Electrostatic potential and counterion partition between flat and spherical interfaces. Journal of Chemical Physics, v. 150, n. 7 FEB 21 2019. Web of Science Citations: 0.