The Short Series of the Oxygen-Poor Lanthanide Oxide Selenides M10OSe14 with M = La–Nd

Crystals

Frank A. Weber¹  Christian M. Schurz¹  Susanne Frunder¹  Charlotte F. Kuhn¹ 

[1]Institute for Inorganic Chemistry, University of Stuttgart, Pfaffenwaldring 55, Stuttgart D-70569, Germany

关键词: lanthanides;    oxide selenides;    crystal structures;    band gaps;    synthesis;   

DOI  :  10.3390/cryst2031136

来源: mdpi

【 摘 要 】

Single crystals and phase pure samples of oxygen-poor ternary lanthanide oxide selenides with the composition M₁₀OSe₁₄ (M = La–Nd; tetragonal, I4₁/acd; a = 1592.0–1559.8 pm, c = 2106.5–2062.9 pm) could be obtained by reacting the corresponding metals, selenium and selenium dioxide as oxygen source. Their crystal structures are isotypic with Pr₁₀OS₁₄ and thus contain isolated [OM₄]¹⁰⁺ tetrahedra (d(O^2-–M³⁺) = 243–248 pm) embedded in a complex anionic {[M₆Se₁₄]^10–} lanthanide selenide matrix (d(M³⁺-Se^2-) = 288-358 pm). All three crystallographically independent M³⁺ cations exhibit eight contacts to chalcogenide anions (O^2– and/or Se^2–) resulting in the formation of bicapped trigonal prismatic coordination polyhedra. The optical band gaps of the oxide selenides M₁₀OSe₁₄ amount to values between 1.89 and 2.04 eV indicating wide band-gap semiconductors.

【 授权许可】

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© 2012 by the authors; licensee MDPI, Basel, Switzerland.