The program can be used to generate any set of atomic or molecular basis functions. As an illustrative example, in section 4.3.1 there is an example of how to generate a set of molecular basis set describing Rydberg orbitals for the benzene molecule. The reader is referred to this example for more details. Finally, the program needs one file for wave function containing the formated set of natural orbitals.
CENTer defines the atom label for which the basis set is to be generated.
SETS keyword indicates that the next line of input contains the number of sets to be used in the averaging procedure and WEIGhts defines the relative weight of each one of the previous sets in the averaging procedure. Three natural orbital files are expected, containing the natural orbitals for the neutral atom, the cation, and the anion. Figure 3.17 .