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The AZn2Sb2 (Pm1, A = Ca, Sr, Eu, Yb) class of Zintl compounds has shown high thermoelectric efficiency (zT∼ 1) and is an appealing system for the development of Zintl structure–property relationships. High temperature transport measurements have previously been conducted for all known compositions except for SrZn2Sb2; here we characterize polycrystalline SrZn2Sb2 to 723 K and review the transport behavior of the other compounds in this class. Consistent with the known AZn2Sb2 compounds, SrZn2Sb2 is found to be a hole-doped semiconductor with a thermal band gap ∼ 0.27 eV. The Seebeck coefficients of the AZn2Sb2 compounds are found to be described by similar effective mass (m* ∼ 0.6 me). Electronic structure calculations reveal similar m* is due to antimony p states at the valence band edge which are largely unaffected by the choice of A-site species. However, the choice of A-site element …