The ternary antimonides ZrSi δ Sb 2-δ , HfGe δ Sb 2-δ , and ZrGe δ Sb 2-δ were prepared by annealing of the elements in stoichiometric ratios below 800 °C. ZrSi δ Sb 2-δ was earlier erroneously described as the binary "β-ZrSb 2 ", which does not exist as such, because the incorporation of tetrel atoms is necessary for the formation of this structure. ZrSi δ Sb 2-δ has a small yet significant phase width with at least 0.066(7) e δ e 0.115(3), whereas the Ge analogues exist with larger tetrel concentration, i.e., ZrGe 0.211(5) Sb 1.789 and HfGe 0.205(6) Sb 1.795 . The whole series of title compounds crystallizes in the Co 2 Si type (space group Pnma), with lattice dimensions of, e.g., for ZrGe 0.211(5) Sb 1.789 , a ) 730.4(1) pm, b ) 395.13(6) pm, c ) 957.6(2) pm, V ) 0.27635(7) nm 3 , Z ) 4. The anionic substructure comprises infinite ribbons formed by the atom sites Q1 and Sb2, with Q1 being mixed occupied by Si or Ge and Sb atoms. These ribbons exhibit Q1−Q1 single bonds and Q1−Sb2 "half" bonds. Assuming the validity of the 8 − N rule, one can assign seven valence-electrons to Sb2 but only five to Q1, which might explain the preference of the tetrel atoms for the latter site.