Quantum theory and molecular structure

Abstract

An attempt is made to refine the classical concept of molecular structure in the light of quantum theory. It is argued that a definite molecular structure can only be associated with quantum states that are intrinsically time-dependent and therefore need not manifest the full symmetry implied by the relativity principle; conversely if a molecule is definitely observed in an eigenstate of its associated molecular Schrödinger equation, a molecular structure description is inappropriate. The theme of the article is illustrated with examples drawn from spectroscopy, dielectric phenomena, electron scattering, stereoisomerism and optical activity.