The stable structures of iron pnictides AFeAs (AÂ = Â alkali and alkaline-earth metals): A first principles study

► Compounds AFeAs (A = K, Rb, Be, Mg, Ca, Sr, Ba) and K3FeAs are stable. ► Stable materials show different magnetic ground states. ► KFeAs, RbFeAs, SrFeAs, BaFeAs and K3FeAs may be superconductors.