A coefficient describing the position of this thing is multiplied by the enthalpy of reaction in a principle which observes a proportionality between (*) activation energies and enthalpies of reaction among reactions of the same family.
[NOTE TO MODERATOR, DO NOT READ OUT LOUD: "ligand" is pronunced "LIG-uhnd" or "LIE-gand"] A theory of and named for these things has a variational type that allows the position of the dividing surface to fluctuate. Among ligand replacement reactions, ligand-dissociative mechanisms are notable for having two of these, whereas ligand-associative mechanisms have only one. A coefficient describing the position of this thing is multiplied by the enthalpy of reaction in a principle which observes a proportionality between (*) activation energies and enthalpies of reaction among reactions of the same family. This configuration is often marked by a double dagger on potential energy diagrams, and it more closely represents the species in a reaction that is more similar to itself in free energy, according to Hammond's postulate. For 10 points, name this configuration of a chemical reaction, defined as local maxima along a reaction coordinate.
[NOTE TO MODERATOR, DO NOT READ OUT LOUD: "ligand" is pronunced "LIG-uhnd" or "LIE-gand"]
transition state