Indirect‐Forbidden Exciton Transitions in AgBr

Abstract

Observation of low temperature resonant Raman scattering in AgBr involving the TA(L) momentum-conserving phonon for the first time, allows symmetry-forbidden indirect exciton transitions to be studied in silver halides. From analyzing the energy dependence of scattered intensity, in terms of impurity trapping and intra-and intervalley exciton scattering, relative scattering probabilities are determined for these relaxation processes.

Relativistic Self-Consistent $GW$: Exact Two-Component Formalism with One-Electron Approximation for Solids

“…Having established the quality of the X2C1e approximation, we now show results from fully self-consistent finite-temperature GW perturbation theory and compare them with available experimental data [84][85][86][87][88]. We emphasize that our results are fully self-consistent and conserving solutions of Hedin's equations and contain no further approximations such as quasi-particle or G 0 W 0 approximations.…”

“…The maximum bandgap widening found in AgCl is about 3.5 eV compared to the non-relativistic DFT result. As compared to experiment, non-relativistic scGW consistently overestimates the band gaps by up to 2 eV [84][85][86]88].…”