[Ge4O6Te4]4—, an Adamantanoid Oxotellurido Germanate(IV) with a Central Ge4O6 Core

Mn(en)₃]₂Ge₄O₆Te₄]·1.5en ( 1 ) and (enH)₃Mn(en)₃]₃Ge₄O₆Te₄]₂I·4.7en ( 2 ) may be prepared at 150 °C by solvothermal reaction of elemental Ge and Te with Mn(OOCCH₃)₂ ·4H₂O in the presence of CH₃)₄N]I as a mineralizer in respectively superheated ethylenediamine (en) or an en/CH₃OH (3:2) mixture. Both contain the novel Ge₄O₆Te₄]^4— anion with a central adamantanoid Ge₄O₆ core and four terminal Te atoms and represent the first examples of such a mixed M₄E₆E₄′]^4— anion (M = Si‐Sn; E = O‐Te). As a result of their increased polarity, the Ge‐Te bonds of 2 are markedly shorter (2.438 — 2.462Å) than those previously reported for telluridogermanates(IV).