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Perturbation theory

S Hirata, A Doran, P Knowles, J Ortiz, One-particle many-body Green's function theory: Algebraic recursive definitions, linked-diagram theorem, irreducible-diagram theorem, and general-order algorithms, JCP 147, 044108 (2017) – doi

S Hirata, X He, M R Hermes, S Y Willow, Second-Order Many-Body Perturbation Theory: An Eternal Frontier, JPCA 118, 655 (2014)

S Grimme, Improved second-order Moller-Plesset perturbation theory by separate scaling of parallel- and antiparallel-spin pair correlation energies, JCP 118, 9095 (2003) – SCS-MP2