Direct comparison of many-body methods for realistic electronic Hamiltonians

Abstract : A large collaboration carefully benchmarks 20 first principles many-body electronic structure methods on a test set of 7 transition metal atoms, and their ions and monoxides. Good agreement is attained between the 3 systematically converged methods, resulting in experiment-free reference values. These reference values are used to assess the accuracy of modern emerging and scalable approaches to the many-electron problem. The most accurate methods obtain energies indistin- guishable from experimental results, with the agreement mainly limited by the experimental uncer- tainties. Comparison between methods enables a unique perspective on calculations of many-body systems of electrons.