Real-Space Stochastic GW Calculations Benchmark on GW100

Stochastic implementation of GW is a linear scaling method, ideally suited for calculating quasiparticle energies of large systems. This approach uses the stochastic resolution of identity to represent Green's function as a product of a randomly generated orbital at time zero and an evolved random orbital at a later time. It employs real time propagation of stochastic functions to obtain screened coulomb response function. The response function is efficiently stored using stochastic compression. We have implemented the stochastic GW method in real-space density functional theory code PARSEC. We have benchmarked our stochastic GW implementation on GW100 set against the results obtained from the NanoGW code [1]. We find that our results are in good agreement with the results obtained from the NanoGW code.

[1] W. Gao, and J. Chelikowsky, J. Chem. Theory Comput. 15, 5299 (2019)