Author(s): Marc Aichner, Matteo Gatti, and Lucia Reining Excitonic effects dominate absorption and loss spectra in many materials. However, they are hard to access computationally, because of the cost of first-principles calculations and because of the scarce reliability of simple approximations. We overcome both limitations by combining a part of the ele… [Phys. Rev. Lett. 137, 126901] Published Mon Sep 14, 2026