ABSTRACT
A need for quantum information measures combining the probability and current contributions is emphasized and continuity relations are summarized. Resultant gradient information accounts for the classical (probability) and nonclassical (phase) contributions and reflects the kinetic energy content of molecular electronic state. The phase-information description enables one to distinguish the hypothetical states of the mutually bonded (entangled) and nonbonded (disentangled) reactants in donor-acceptor systems. This generalized information-theoretic perspective is applied to chemical reactivity phenomena within the grand-ensemble description of thermodynamic conditions in open molecular systems. The physical equivalence of variational principles for the system electronic energy and resultant gradient information is demonstrated. The virial theorem decomposition of energy profiles is used to index the Hammond rule of reactivity theory, information changes in chemical reactions are addressed, and charge transfer between reactants is explored. The 2 frontier-electron approach to molecular interactions is used to rationalize the Hard (Soft) Acid and Bases (HSAB) principle of structural chemistry, and the rule implications for the intra- and inter-reactant communications are commented upon.
