Design of a versatile force field for the large-scale molecular simulation of solid and liquid OMCTS

We developed a new, versatile force field for the molecular simulation of octamethylcyclotetrasiloxane (OMCTS) both in the solid and liquid phases. From a series of molecular dynamics simulations, we obtain good agreement with the experimental lattice constants, sublimation enthalphy, and molecular packing of the crystal. The experimental density, diffusion coefficient, and shear viscosity of this van der Waals liquid in the range 300-440 K are well reproduced as well. The new force field can be thus employed in the large-scale molecular simulation of liquid OMCTS where structural details are important in determining the collective properties of the system.