PI 

Description

PI analyzes the density matrix resulting from the SCF procedure to output the composition of each atom-atom interaction in terms of sigma and pi bonds. The resulting description is composed of the following basis functions: s-sigma, p-sigma, p-pi, d-sigma, d-pi, d-dell. The diagonal terms give the hybridization state, so that an sp² hybridized system would be represented as s-sigma 1.0, p-sigma 2.0, p-pi 1.0.