Computer Simulation Of Vapor-Liquid Equilibria For Model And Real Polar Fluids

With the development of modern computers, computer simulation has been becoming an important method in modern statistical mechanics and molecular thermodynamics. By performing computer simulation, many physical phenomena and their molecular background can be discovered and interpreted. Moreover, computer simulation provides a direct route from microscopic details of a system to macroscopic properties of experimental interest.In this work, both the pure and mixture Stockmayer (SM) fluids have been simulated by using the Gibbs ensemble Monte Carlo (GEMC) method. The effects of dipolar interactions of the molecules to the VLE of the fluids have been investigated. Extensive simulation data for the mixtures have been obtained, which are of importance in the development of the thermodynamic models for such systems. The simulation results show that the phase coexistence properties of polar fluids are sensitive to the molecular dipolar interactions. A comparison between the results of this work and those obtained with an angle-averaged approximation for the long-ranged dipolar interaction indicates that this approximation is not suitable for mixtures in which the dipolar interaction is dominant.The quasi-two-dimensional (2D) SM model has been simulated, in which the center of mass of the molecules is confined on a plane, while the dipole of the molecules can rotate freely in the three dimensional (3D) space. This model entails the essential characteristics of systems such as dipolar molecules physisorbed on a solid surface, or a Langmuir monolayer consisting of short-chain molecules with a dipolar tail. The GEMC technique has been employed to determine the VLE of the model...