A rigorous framework for embedding of quantum systems with long-range interactions

We will describe a rigorous RPA-based downfolding of long-range interactions that is suitable for broad quantum embedding applications. Treating these long-range interactions in an efficient way is (we believe) the biggest conceptual and practical limitation of quantum embedding of strongly correlated systems to local fragments. Current approaches often rely on uncontrolled approximations and lack the systematic improvability to ensure trust and internal checks on the validity of results. The approach will relate to a number of existing methodologies in the field, and describe a new framework for embedding of materials and molecules with a faithful description of both long-range Coulomb interactions and strongly correlated local degrees of freedom.