Thermophysical Properties of Fluids: multi-scale modelisation approaches

Gibbs code is a general Monte Carlo simulation code. It has been developped jointly by Université Paris Sud , CNRS and IFPEN. The Gibbs code is aimed at computing the equilibrium properties of fluids by molecular simulation, using a Monte Carlo method in cubic, parallepipedic or even non orthorhombic simulation boxes.

Main features

  • Determination of phase properties: statistical ensembles NVT, NPT, μVT. The NVT and μVT determinations may be done while imposing an external field defined on a grid. Among other applications, it allows to simulate the adsorption of molecules in microporous crystalline solids of cubic, orthorhombic or triclinic structre.
  • Calculation of phase equilibria, either two-phase (L-V, L-L) or multiphase (L-L-V. . . ), using the Gibbs Ensemble at imposed pressure or imposed global volume.
  • Calculation of fluid solubility in polymeric materials in the osmotic ensemble (semi-grand canonical).
  • Calculation of chemical equilibria, using the Reaction Ensemble at imposed pressure or imposed volume, in either one-phase, two-phase or multiphase simulation. It is also possible to simulate a chemical equilibrium involving a pseudo-particle, as well as a virtual solid phase.
  • Calculation of interfacial tensions.
  • Calculation of vapour pressures and saturated properties of given-composition liquid mixtures in the Boiling Point Ensemble
  • Thermodynamic integration

Other specific features

  • Communication with other simulation codes to account for quantum effects e.g. using Gaussian code
  • Hanling united atoms forcefield, including the Anisotropic United Atoms model.
  • Simulations using coarse grained potentials
  • Optimized for multicore machines with parallel programming using both MPI and OpenMP librairies.