Beyond the First Year Level

Some of the topics that we introduce beyond the first-year level need not be repeated here, for example, molecular mechanics for organic chemistry studentsi and numerical solutions to the Schrodinger equation for physical chemistry students. These are topics that are covered adequately in other sections of this chapter, with applications at the three other institutions. 

There is a very extensive literature for the electronic structure of two-electron atoms and ions, including several articles that have been published in the Journal of Chemical Education. If the chemistry student understands some of the problems involved in describing the behavior of how electrons interact in an atom, he or she will be much better served to understand their behavior in molecules. In this section, we consider only the closed-shell ground state of two-electron systems. 

We have developed a software application, ATOMPLUS,i38 which can be used in a turnkey fashion to illustrate theoretical features of two electron atoms, such as basis set effects, correlation energy, virial ratio, variational principle, and multideterminantal wavefunction. The program is provided in executable format for either the IBM or Macintosh platform. The source code can be obtained from Project Seraphim and, since it is written in FORTRAN 77, it compiles readily on other platforms. 

The first wavefunction is the simple single-zeta Slater-type orbital, and the Hartree theoretical model is adopted. The approach that we use to solve the 

Of course, one does not need to use a dedicated computer program such as ATOMPLUS to solve the Schrodinger equation for this example, since the integrals that arise are very simple. We already have discussed the T and integrals above. Allowing the two electrons to have different 4 values compli- 

---