In the first part of this thesis, molecular dynamics (MD) simulation is used to study the dynamics and traort properties of twelve room temperature ionic liquids of the 1-alkyl-3-methylimidazolium [amim] + (alkyl = methyl, ethyl, propyl, and butyl) family with PF 6 ? , NO 3 ? , and Cl ? counterions. The goal of first part of research is to provide molecular level understanding of the traort coefficients of these liquids as guidance to experimentalists on choosing anion and cation pairs to match required properties of ionic liquid solvents. By employing of trajectory-averaging, the ionic diffusion coefficients determine and evaluate from the linear slope of mean-square displacements (MSDs) and from the integration of the velocity autocorrelation functions (VACFs). The electrical conductivity is calculated from the Nernst-Einstein and Green-Kubo formulas and the viscosity is also determined from the Stokes-Einstein relation. Simulation results can show good agreement with experiment in predicting relative trends in the traort coefficients and determining the role of the cation and anion structure on the dynamical and traort behavior of this family of ionic liquids. Simulations of this thesis show that the major factors determining the magnitude of the self-diffusion, electrical conductivity, and viscosity are the geometric shape, ion size, and the delocalization of the ionic charge in the anion. In the second part of thesis, we use MD simulation to study the structure, dynamics, and congruent melting of the equimolar compound of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide with benzene, [emim][NTf 2 ]•C 6 H 6 . The calculated melting point of 290 ± 4 K is in excellent agreement with the experimental melting point of 288 K.