Transitioning High-Accuracy Electronic Structure Methods from Molecules to the Solid State

This presentation discusses ongoing work to transfer trusted computational and theoretical tools that are traditionally used in the molecular regime to the rapidly growing field of solid state physics. Specifically, Equation of Motion Coupled Cluster (EOM-CC) is compared to the current state-of-the-art method, the so-called GW approximation for the GW100 test set. Ongoing challenges to the implementation of periodic EOM-CC including finite size effects, basis set effects, and pseudopotentials to reduce computational complexity will be addressed. Preliminary results indicate that this problem is not trivial and requires consideration of many inputs and extrapolation schemes in order to achieve reliable results. In addition to these computational schemes, a systematic hierarchy of approximations is introduced to quantitatively gauge computational cost and accuracy trade-offs, exploring theoretical errors in addition to computational errors.