[K(222-crypt)]2TeSe10 und [Ba(222-crypt)(en)]TeSe10·en0,5: Verbindungen mit einem neuen spirozyklischen TeSe10 2--Polychalkogenid-Anion / [K(222-crypt)]2TeSe10 and [Ba(222-crypt)(en)]TeSe10 · en0.5: Compounds with a New Spirocyclic Polychalcogenide Anion TeSe10 2-

Abstract

Attempts to prepare selenotellurates with coordination numbers greater than three for the tellurium atom led to the title compounds [K(222-crypt)]2TeSe10 and [Ba(222-crypt)(en)]TeSe10·en0.5 with a new mixed polychalcogenide anion TeSe10 2-. The crystal structures of both compounds contain four-coordinate tellurium with two bidentate Se5 forming a spirocyclic arrangement with Te as the common spiro atom in a planar, almost square coordination. The potassium cation is cryptated by the macro-bicyclic aminopolyether 222-crypt (CN 8), whereas the barium cation is coordinated by the cryptand and a further solvate molecule of ethylenediamine, resulting in a total coordination number of 10. [K(222-crypt)]2TeSe10: PI, a = 1333.3(6) pm, b = 1214.6(6) pm, c = 1078.3(4) pm, α = 95.80(6)°, β = 90.18(6)°, γ = 115.20(6)°, R = 0.073; [Ba(222-crypt)(en)]TeSe10 · en0.5: PĪ, a = 1802.2(6) pm, b = 1132.1(4) pm, c = 1049.4(4) pm, α = 79.80(6)°, β = 87.27(6)°, γ = 84.63(6)°, R = 0.076.