Theoretical insights into inorganic antiperovskite nitrides (X3NA: X = Mg, Ca, Sr, Ba; A = As, Sb): An emerging class of materials for photovoltaics

Antiperovskite nitrides are potential candidates for applications harvesting solar light. With a comprehensive state-of-the-art approach combining hybrid density-functional theory, many-body perturbation theory, the Wannier-Mott model, density-functional perturbation theory, and the Feynman polaron model, we explore excitonic and polaronic effects in ${\mathit{X}}_{3}\mathrm{N}A$ ($X$ = Mg, Ca, Sr, Ba; $A$ = Sb, As). For all, we uncover a significant influence of the ionic dielectric screening on the static dielectric constant. Small exciton binding energies, weak electron-phonon coupling, and high charge-carrier mobilities facilitate enhanced charge transport in ${\mathrm{Mg}}_{3}\mathrm{NSb}$, ${\mathrm{Ca}}_{3}\mathrm{NSb}$, ${\mathrm{Sr}}_{3}\mathrm{NSb}$, and ${\mathrm{Ba}}_{3}\mathrm{NSb}$. Our results highlight the potential of these nitrides as optimal candidates for efficient photovoltaic absorbers.