Based on crystal chemistry and density functional theory calculations, a novel family of tetragonal (P4 2 /mnm) boron pnictides BX with crb topology with X element belonging to group 5A (X = N, P, As, Sb, Bi). has been predicted. From a crystallographic point of view, these phases exhibit a square B2X2 motif the edge-sharing BX4 tetrahedra connected via corners. All new crb BX phases were found to be cohesive, and mechanically stable from elastic constants. As can be seen from the charge density projections, the BX family exhibits different types of chemical bonding, changing from nitride BN to ionocovalent behavior for P and As, and finally to borides in the case of Sb and