  Antiperovskite materials are well known for their high thermoelectric
performance and gained huge research interest. Here, we report the structural
stability and transport properties of Sr$_3$AsN from a precise first-principles
study. The calculated equilibrium lattice parameters are in a good agreement
with the available data. We find that Sr$_3$AsN is a mechanically,
energetically and dynamically stable at ambient condition. Our calculated
electronic structure indicates that it is a direct bandgap semiconductor, with
a value ~1.2 eV. Sr-4d and N-2p orbitals mainly formulate the direct bandgap.
This antiperovskite possesses a high Seebeck coefficient. Although its lattice
thermal conductivity is comparatively low, electronic thermal conductivity is
very high. The calculated maximum TE figure of merit is 0.75 at 700 K,
indicating that it is a potential material for thermoelectric applications.
