Electron propagator method with a multiconfigurational second-order perturbation theory wave function as the initial state in the fermion operator block

Different forms of wave functions were used as the initial state in Green's function methods. An electron propagator method that uses a multiconfigurational-based second order perturbation theory wave function as the reference state was developed. With this new method a better initial state is used in the electron propagator calculations. CASPT2 is specifically designed to handle both dynamical and nondynamical electron correlation effects.

Electron propagator method with a multiconfigurational second-order perturbation theory wave function as the initial state in the fermion operator block Academic Article