About the Concept of Molecular Structure

Abstract

The concept of molecular structure is one of the mostimportant concepts of chemistry. In fact, molecular structure is closelyrelated to the concept of chemical substance and its set of properties, and it isthe main factor in the explanation of reactivity. In fact, much of the behaviorof substances is explained in terms of the structure of their componentmolecules. This may explain why people tend to take the notion of molecularstructure for granted. However, the problem begins already when it comes tospecifying the concept, since there is no clear definition of ‘molecularstructure’ valid for all chemistry. The purpose of the present article is toshow that the term ‘molecular structure’ subsumes very different notions, whichdepend on how the molecule and its components are conceived, and each of whichbrings its own difficulties. In particular, we will focus on how the moleculeand its structure are devised from a classical view and from aquantum-mechanical view, and will discuss the different problems related withmolecular structure that arise in each case.