Application of the Theory of Atoms in Molecules

Abstract

<p>This thesis applies the theory of atoms in molecules to a series of hydrocarbon molecules. The atoms of theory are those that satisfy the quantum boundary condition. It is shown that regions of real space that obey this quantum boundary condition exist and the quantum mechanics which governs the total system also governs the atomic subsystems. These atoms of theory can be identified as the atoms of chemistry. An important result of this is that the total value of a property is a sum of the atomic contributions. Standard group energies can be defined. Using these facts, the additivity scheme for the homologous series of hydrocarbons, CH₃(CH₂)mCH₃, starting at m=0 is recovered. The standard group energies are used in the prediction of strain energies. Finally it is shown that the Laplacian of the charge distribution is able to recover both the geometry model of Lewis and VSEPR theory as well as chemical reactivity.</p> <p>Chapter I gives an overview of the basic theory itself while Chapter II examines the charge density for evidence of the atoms of theory. In Chapter III and IV a series of hydrocarbon molecules are investigated using the theory of atoms in molecules. Chapter V uses the Laplacian of the charge density to recover the Lewis and VESPR models and to provide a deeper understanding of the bridgehead bond of propellane molecules.</p>