Speaker: Fabian Maximilian Faulstich
Title: MPCC: A Scalable Coupled-Cluster Embedding Framework for Accurate Quantum Chemistry
Abstract: We present the MPCC (Møller-Plesset Coupled-Cluster) method, a static quantum embedding framework formulated at the level of the coupled-cluster projection equations, in which a high-level fragment is coupled self-consistently to a low-level environment. The method achieves near coupled-cluster accuracy for local observables and is systematically improvable with fragment size. To enable applications to large systems, we reduce the cost of the environment solver using density fitting in combination with a canonical polyadic decomposition of the amplitude tensors, alleviating the computational bottleneck. Finally, we extend the framework beyond CCSD by incorporating triple excitations, enabling accurate treatment of strongly correlated systems such as transition-metal complexes.