biostudies-literatureIshtiyak MLouisiana State UniversityBasic Energy SciencesLouisiana Board of RegentsDivision of Materials Research20226-20239https://www.ebi.ac.uk/biostudies/studies/S-EPMC11523219biostudies-literatureUnknown63(43)Two novel quaternary oxyarsenides, Eu₈Zn₂As₆O and Eu₁₄Zn₅As₁₂O, were synthesized through metal flux reactions, and their crystal structures were established by single-crystal X-ray diffraction methods. Eu₈Zn₂As₆O crystallizes in the orthorhombic space group <i>Pbca</i>, featuring polyanionic ribbons composed of corner-shared triangular [ZnAs₃] units, running along the [100] direction. The structure of Eu₁₄Zn₅As₁₂O crystallizes in the monoclinic space group <i>P</i>2/<i>m</i> and its anionic substructure can be described as an infinite "ribbonlike" chain comprised of [ZnAs₃] trigonal-planar units, although the structural complexity here is greater and also amplified by disorder on multiple crystallographic positions. In both structures, the O^2- anion occupies an octahedral void with six neighboring Eu²⁺ cations. Formal electron counting, electronic structure calculations, and transport properties reveal the charge-balanced semiconducting nature of these heteroanionic Zintl phases. High-temperature thermoelectric transport properties measurements on Eu₁₄Zn₅As₁₂O reveal relatively high resistivity (<i>ρ</i>_500K = 8 Ω·cm) and Seebeck coefficient values (<i>S</i>_500K = 220 μV K^-1), along with a low concentration and mobility of holes as the dominant charge-carriers (<i>n</i>_500K = 8.0 × 10¹⁷ cm^-3, <i>μ</i>_500K = 6.4 cm²/V s). Magnetic studies indicate the presence of divalent Eu²⁺ species in Eu₁₄Zn₅As₁₂O and complex magnetic ordering, with two transitions observed at <i>T</i>₁ = 21.6 K and <i>T</i>₂ = 9 K.Inorganic chemistryAdvancing Heteroanionicity in Zintl Phases: Crystal Structures, Thermoelectric and Magnetic Properties of Two Quaternary Semiconducting Arsenide Oxides, Eu&lt;sub&gt;8&lt;/sub&gt;Zn&lt;sub&gt;2&lt;/sub&gt;As&lt;sub&gt;6&lt;/sub&gt;O and Eu&lt;sub&gt;14&lt;/sub&gt;Zn&lt;sub&gt;5&lt;/sub&gt;As&lt;sub&gt;12&lt;/sub&gt;O.PMC11523219LEQSF (2024-27)-RD-A-061904636DE-SC0008885Bobev SIshtiyak MThipe BYoung DPWomack FAdams PWatts SRBai XBaranets SfalseAdvancing Heteroanionicity in Zintl Phases: Crystal Structures, Thermoelectric and Magnetic Properties of Two Quaternary Semiconducting Arsenide Oxides, Eu&lt;sub&gt;8&lt;/sub&gt;Zn&lt;sub&gt;2&lt;/sub&gt;As&lt;sub&gt;6&lt;/sub&gt;O and Eu&lt;sub&gt;14&lt;/sub&gt;Zn&lt;sub&gt;5&lt;/sub&gt;As&lt;sub&gt;12&lt;/sub&gt;O.Two novel quaternary oxyarsenides, Eu₈Zn₂As₆O and Eu₁₄Zn₅As₁₂O, were synthesized through metal flux reactions, and their crystal structures were established by single-crystal X-ray diffraction methods. Eu₈Zn₂As₆O crystallizes in the orthorhombic space group <i>Pbca</i>, featuring polyanionic ribbons composed of corner-shared triangular [ZnAs₃] units, running along the [100] direction. The structure of Eu₁₄Zn₅As₁₂O crystallizes in the monoclinic space group <i>P</i>2/<i>m</i> and its anionic substructure can be described as an infinite "ribbonlike" chain comprised of [ZnAs₃] trigonal-planar units, although the structural complexity here is greater and also amplified by disorder on multiple crystallographic positions. In both structures, the O^2- anion occupies an octahedral void with six neighboring Eu²⁺ cations. Formal electron counting, electronic structure calculations, and transport properties reveal the charge-balanced semiconducting nature of these heteroanionic Zintl phases. High-temperature thermoelectric transport properties measurements on Eu₁₄Zn₅As₁₂O reveal relatively high resistivity (<i>ρ</i>_500K = 8 Ω·cm) and Seebeck coefficient values (<i>S</i>_500K = 220 μV K^-1), along with a low concentration and mobility of holes as the dominant charge-carriers (<i>n</i>_500K = 8.0 × 10¹⁷ cm^-3, <i>μ</i>_500K = 6.4 cm²/V s). Magnetic studies indicate the presence of divalent Eu²⁺ species in Eu₁₄Zn₅As₁₂O and complex magnetic ordering, with two transitions observed at <i>T</i>₁ = 21.6 K and <i>T</i>₂ = 9 K.2024-01-01T00:00:00Z2024 Oct2025-04-04T01:02:37.813Z2025-04-04T01:02:37.813ZS-EPMC115232193890445410.1021/acs.inorgchem.4c01580