Irrotational and vortex fields in the theory of molecular dynamics

Abstract

Abstract The theory of molecular diffusion is extended to include consideration of the position vector r of the centre of mass of each molecule in the ensemble. This implies automatically that the interaction of rotation and translation must be considered in the treatment of non inertial accelerations in the molecular ensemble. This leads to a consideration of vortex and irrotational fields in the theory of molecular dynamics in the laboratory frame (x,y,z) and in the moving frame (1,2,3) defined by the frame of the principal molecular moments of inertia. Computer simulations of supercooled liquid water are used to determine the nature of the time dependence of some of these autocorrelation functions involved in the development of the theory. This in turn might lead to a method of linking the ideas of molecular dynamics and hydrodynamics in the theory of fluids.