Exchange of Molecular Parts between Coordination Compounds at Equilibrium
Because of the availability of modern analytical and computative methods, particularly nuclear magnetic resonance and high-speed computers, it is now possible to investigate chemical systems consisting of various sizes and shapes of molecules at equilibrium with each other. It is common in inorganic chemistry for molecules to be sufficiently labile so that during the standard preparative laboratory operations, an equilibrium mixture is obtained via scrambling reactions. in this kind of reaction, the total number of bonds of any type remains constant but the atoms are rearranged. Thus, to the extent that bond energies are additive, scrambling reactions should have zero enthalpy and hence be entropy controlled.