Abstract

I will focus on our recent methodological advances that allow us to perform converged path integral simulations of condensed phase systems at coupled cluster accuracy as demonstrated for liquid water. This progress is enabled by generating many-body interactions in the framework of high-dimensional neural network potentials that have been trained based on CCSD (T) electronic structure calculations of finite systems, thus transferring “Gold Standard” quantum-chemical accuracy from the gas to the liquid phase. I will show how that Coupled Cluster Molecular Dynamics method, CCMD , can be applied to quantify H/D isotope effects on key structural and dynamical properties of water, thereby resolving ongoing controversies.