.. _`sec:methods`: =============================== Theoretical Methods: SCF to FCI =============================== Several electronic structure methods are available in the |PSIfour| package, from Hartree--Fock molecular orbital theory to coupled-cluster theory to full configuration interaction. This section introduces the methods available and some of their most common input parameters. A complete list of standard keywords is provided in Appendix :ref:`apdx:options_c_module`. .. toctree:: :maxdepth: 2 notes_c scf dft dcft dfmp2 cc fnocc occ psimrcc detci sapt adc relativistic optking oeprop thermo