Quantum information description of reactive systems
Roman F. Nalewajski · Jagiellonian University Repository (Jagiellonian University) · 2014
Information Theory (IT) of molecular electronic states is applied to describe equilibria in separate reactants and reactive system as a whole. It uses the resultant (quantum) measures of the information content in electronic states, determined by both the classical (probability/density) functionals and their non-classical (phase/current)-related complements. The intra- reactant (fragment) equilibrium state in the separate reactant is uniquely characterized by its equilibrium phase related to its own electron distribution, while the inter-reactant (molecular) equilibrium state reflects the stationary electron density of the whole reactive system. The probability currents of the non-bonded reactants, e.g., the isolated fragments or their mutually- closed analogs in the system “promolecular” reference, and of the bonded (mutually-open) fragments in the whole reactive system, are compared to identify the current-promotion of these subsystems. The illustrative case of the two-orbital (2-electron) system is examined in some detail to generate the combination formula for the overall current and to identify its additive and non-additive components. Electron communications between reactants are examined and IT descriptors of the multiplicity and covalent/ionic composition of chemical bonds are related to the additive and non-additive information contributions in local and atomic orbital resolutions.