It is probably unfortunate that physics and chemistry ever were separated. Chemistry is the science of atoms and of the way they combine. Physics deals with the interatomic forces and with the large-scale properties of matter resulting from those forces. So long as chemistry was largely empirical and non-mathematical, and physics had not learned how to treat small-scale atomic forces, the two sciences seemed widely separated ... Now that statistical mechanics has led to quantum theory and wave mechanics, with its explanations of atomic interactions, there is really nothing separating them any more .... [However,] for want of a better name, since Physical Chemistry is already preempted, we may call this common field Chemical Physics.1