This manuscript is Volume II of the program to axiomatize chemistry within the established global-realist framework. Its purpose is to define molecules and chemical bonds without circular appeal to primitive notions such as "shared electron pairs" or "molecular orbitals." Building directly upon the one-center atomic theory of Volume I, a molecule is defined as a finite-energy multicenter bound state whose nuclei are jointly constrained by a self-consistent, shared electronic disturbance field, and which constitutes a local minimum on the nuclear shape space relative to the separated-channel limit. A chemical bond is subsequently defined as an energy-stabilized, internuclear bridge sustained by this shared disturbance field, identified by a variational criterion of bridge persistence. On this basis, the Born–Oppenheimer potential energy surface, molecular geometry (bond lengths and angles), and normal-mode vibrations are derived as consequences of the same energy-minimization principle. Standard quantum-chemical approximations, including LCAO, Hartree–Fock, and Density Functional Theory, are shown to be specific variational restrictions or closures of this underlying functional, thereby unifying them under a single realistic ontology. The framework is extended to encompass intermolecular forces, metallic bonding and band theory, molecular spectroscopy and photochemistry, and relativistic effects in heavy-element chemistry. The volume establishes a logically closed, non-circular derivation of molecular structure and bonding from lower-level physical objects, completing the static structural layer of chemistry.
Jianming Wang (Sat,) studied this question.