An Introduction to the Electronic Structure of Atoms and Molecules

Dr. Richard F.W. Bader 
Professor of Chemistry / McMaster University / Hamilton, Ontario

1.  The Nature of the Problem
2. The New Physics
  A Contrast of the Old and New Physics
  Probability Amplitudes
  Further Reading
3.  The Hydrogen Atom
4.  Many-Electron Atoms
5.  Electronic Basis for the Properties of the Elements
6.  The Chemical Bond
7.  Ionic and Covalent Binding
8.  Molecular Orbitals
Table of Contour Values

1. One of the more recent experimental methods of studying the nucleus of an atom is to probe the nucleus with very high energy electrons. Calculate the order of magnitude of the energy of an electron when it is bound inside a nucleus with a diameter 1 ´ 10-12 cm. Compare this value with the order of magnitude of the energy of an electron bound to an atom of diameter 1 ´ 10-8 cm. 
Nuclear particles, protons or neutrons have masses approximately 2 ´ 103 times the mass of an electron. Estimate the average energy of a nuclear particle bound in a nucleus and compare it with the order of magnitude energy for an electron bound to an atom. This result should indicate that chemical changes which involve changes in the electronic energies of the system do not affect the nucleus of an atom.