Because the refreshment must be accomplished by computation, there is no need to refresh exactly the same structure every time. This is especially important in representing chemical reactions. The conventional chemical equation on the printed page seems to imply that the reactants proceed directly to products and does not betray the several cycles of thermal vibrations the reactants and products undergo during even the brief course of a reaction or the alignment and phasing of these vibrations that is necessary if the reactants are to achieve the transition complex and cross over the reaction barrier. All this is simply swallowed up in a number called the Arrhenius pre-exponential factor and is nowhere in evidence in the representation of the reaction. One of the most important representational issues in chemistry is still difficult in the electronic medium.
Chemistry is the interaction between molecules.
As one molecule approaches another, its electronic periphery encounters another electronic periphery. The problem is that we must simultaneously present several properties that vary continuously throughout three dimensions. These properties may be mapped to the new electronic dimensions of color and intensity. Several conventions, including partial transparency, isosurfaces, slicing, and contour mapping seem difficult representations at best, but these must be compared to the limited options available to the printed medium in which representation of these properties remains nearly impossible. Finally, the electrons which constitute the chemically reactive periphery of the molecule exist in different energy states and each state has its own distribution and properties.