In this study, we will focus on interpreting the computed band structures of two Yb 14 M Sb 11 compounds: Yb 14 MgSb 11 and Yb 14 AlSb 11 using the Zintl concept in combination with a molecular orbital analysis. We show that the molecular orbitals for structural units (M Sb 4 ) m-, and (Sb 3 ) 7-are easily identified giving clear indication as to which atoms dominate the conduction and valence bands. We discuss how this method can be used to understand and modify the electronic properties of A 14 MX 11 compounds providing strategies to optimize their thermoelectric performance. All first-principles Density Functional Theory (DFT) calculations were performed used the Vienna ab-initio simulation package (VASP) using the projector-augmented wave (PAW) method and an energy cutoff of 500 eV. The 4f electrons of Yb were not treated explicitly as valence electrons following the methodology of Ref. 25. The structures were relaxed with a force convergence criterion of 0.005 eV/ Å with a Γ-centered k-point grid 42 of 3 × 3 × 3. Static calculations were subsequently performed on the relaxed structures with a k-point grid of 5 × 5 × 5 using the tetrahedron method for density of states calculations.