Simulação dos parâmetros geométricos do Sal Triflato de Lítio hidratado utilizando Dinâmica Molecular de Car-Parrinello

Abstract

The lithium trifluoromethanesulfonate (lithium triflate) is a salt that has many technological applicability (lithium battery, polymer blends and electrode support in the production of polymer films), and a high potential for scientific research in molecular dynamics. The Car-Parrinello Molecular Dynamics was used in this study in order to analyze the structure of the salt (lithium triflate) as well as the influence of the solvent (water) on the conformation and structural properties of this salt. Water can be used to produce polymeric films which are also produced with apolar solvents. For the boarding of systems containing hydrated salt or ions was necessary to sketch a box (unitary cell) that allows the representation of the periodic system as a whole, the program used for this purpose was the HyperChem, and this program was used, including, to optimize the geometry of the molecules. In the Quantum Espresso program were carried out molecular dynamics simulations of the systems studied. The results indicated that the lithium triflate presents monodentate structure. Besides resulting in a conformation according to Newman Projection, being that lithium triflate salt has a constant movement (rotate) in the structures (-CF3) and (-SO3) when isolated and in solvated systems, water makes with that the structure of the salt stay rigid. As to the influence of the solvent in the structural properties of lithium triflate, the results showed that the water interferes in the length of the bonds, in the angles and in the diedrals angels.