Neue Oxozincate mit Inselstruktur: K4[ZnO3] Mit einem Anhang über Rb7Na[ZnO3]2

New Nesozincates: K₄ZnO₃], Rb₇NaZnO₃]₂ For the first time A) K₄ZnO₃] and B) Rb₇NaZnO₃]₂ have been prepared (from the binary oxides). They represent the first oxozincates of the alkali metals in which the coordination number of Zn²⁺ is exclusively 3 (carbonate-like groups ZnO₃]). Both oxides crystallize triclinic, space group P1 with A): a = 1103.3(3), b = 881.3(3), c = 698.2(2) pm, α = 109.65(2)°, β = 89.56(2)°, γ = 102.41(3)° and Z = 4, and B): a = 1128.3(3), b = 974.5(3), c = 711,8(2) pm, α = 114.12(2)β, = = 88.46(3)°,γ = 106.48(2)° and Z = 4. Their crystal structures have been determined from single crystal data (four circle diffractometer) and refined to R = 10.1%, R_w = 7.8% (2905 unique I₀(hkl)) and R = 19.5%, R_w = 17.3% (2269 unique I₀(hkl)), respectively. The Madelung Part of Lattice Energy (MAPLE), Effective Coordination Numbers (ECoN) and Mean Fictive Ionic Radii (MEFIR) have been calculated.