Alkalimanganselenide und -telluride A2Mn3X4 – Synthese,Kristall- und Spinstruktur

Alkali Metal Manganese Selenides and Tellurides – Synthesis, Crystal and Spin Structures The compounds Rb₂Mn₃Se₄, Cs₂Mn₃Se₄, Rb₂Mn₃Te₄ and Cs₂Mn₃Te₄ were synthesized by the reaction of alkali metal carbonates with chalcogen and Mn or MnCO₃ in a stream of hydrogen charged with chalcogen. Structural investigations show that all compounds crystallize in isotypic atomic arrangements (Cs₂Mn₃S₄-type, space group Ibam, Z = 4). Additionally neutron diffraction experiments were carried out and yielded the spin structures of Rb₂Mn₃Se₄ and Cs₂Mn₃Se₄ (Shubnikov space group Ibam'). The structural related selenides ALiMnSe₂ and ALiZnSe₂ (A = K, Rb or Cs) were synthesized by analogous reactions. All these compounds are isotypic and crystallize in the BaZn₂P₂-structure type.