Post-HF Correlation

Correlation energy methods improve upon the Hartree–Fock reference by recovering a fraction of the electron correlation energy. OpenQuantum provides:

• Spin-Scaled MP2 — Møller–Plesset perturbation theory to second order, with optional spin-component scaling (SCS-MP2)
• CCSD Convergence — Coupled-cluster singles and doubles, with convergence controls for the CC iterative solver