ABSTRACT
Gaussian functions do not resemble atomic orbitals very closely, but have the great advantage that integrals one encounters in a Roothaan SCF calculation are all relatively easy. The simplest case is the spherical Gaussian function, also known as the Gaussian lobe. In this chapter we detail features of the Gaussian-lobe basis, the foundation of the PCLOBE package. The use of Gaussian basis sets was first developed by Boys [1,2]. His
first examples were H and He which require only s orbitals, of the form shown below.
