<p>The problem of molecular structure occupies a central place in debates concerning the relations between quantum chemistry and quantum mechanics. Traditionally, these discussions have focused on the possibility of deriving well-defined molecular geometries from a strict quantum formalism and on the role of the Born–Oppenheimer approximation. In this paper, it is proposed to reformulate the problem by shifting the focus from molecular structure to the potential energy surface (PES), understood as the entity through which the notions of structure, stability, and reactivity acquire operational significance in quantum chemistry. On the basis of an analysis of the Born–Oppenheimer and Born–Huang formalisms, it is argued that the PES is not directly derived from the molecular Hamiltonian, but rather obtained through a projection procedure onto electronic subspaces defined with respect to fixed nuclear configurations. Finally, it is maintained that the PES can be interpreted as an emergent effective field characterized by novelty and robustness.</p>