Benchmarking the Plasmon-Pole and Multipole Approximations in the Yambo Code Using the GW100 Data Set

Verification and validation of electronic structure codes are essential to ensure reliable and reproducible results in computational materials science. Besides the extensive work on density functional theory, in the field of many-body perturbation theory, the GW100 data set represents a key effort to benchmark and validate methods such as the GW approximation. In this work, we assess the numerical accuracy and convergence behavior of the GW implementation in the yambo code using both the Godby-Needs plasmon-pole model (GN-PPA) and the recently introduced multipole approximation (MPA). Quasiparticle energies are compared against GW100 reference data to evaluate the performance, numerical stability, and consistency of these approaches. Our results show that the GN-PPA approach is in very good agreement with full-frequency methods, further improved by the excellent agreement of the MPA scheme, especially when comparing with plane-wave codes.