Estudos de propriedades termodinâmicas e estruturais dos líquidos etilenoglicol e glicerol utilizando simulação computacional.
Abstract
Ethylene glycol and glycerol are molecular liquids with many
internal degrees of freedom. Rotations along specific chemical bonds allow the
formation of intramolecular hydrogen bonding, leading to several stable
conformational possibilities. Due to the capability of these liquids to form one or
more hydrogen bonding with appropriate solutes, they have been used to verify
the influences of these bonds in the conformational and thermodynamics
properties of molecules. The studies were performed using Molecular Dynamics
methodology implemented in the TINKER package. A combination of the force
fields OPLS-AA (Optimized Potential for Liquid Simulations-All Atoms) and
AMBER was used to represent molecular interactions. Structural and
thermodynamic properties of liquid ethylene glycol in the ensemble NpT at
temperatures of 265 K, 300 K, 350 K and 465 K and 1.0 atm were calculated.
The same study was performed for glycerol at temperatures of 300 K, 400 K and
555 K. Internal rotations along all axes defined by bonds C-O and C-C had been
considered. The formation and behavior of hydrogen bonds was as a function of
time were particularly considered.