| Abstract: | A New Inoferrate(III): K2Na4(FeO3)2] For the first time amber coloured single crystals of K2Na4(FeO3)2] were prepared by heating well ground mixtures of KFeO2 and Na2O (molar ratio Na2O:KFeO2= 1.4:1.0; ?Ag-tube”?, 500 °C/29 d, 400 °C/5 d): Spacegroup Pnma with a = 650.50(6) pm, b = 619.62(5) pm, c = 1020.64(12) pm. K2Na4(FeO3)2] is isotypic to K2Na4(GaO3)2] 2]. The structure has been determined by four-circle-diffractometer data Mo—Kα , 982 of 982 unique I0(hkl), R = 4.56%, Rw = 4.56% (no weight)]; parameters as given in the text. The Madelung Part of Lattice Energy, MAPLE, and the Effective Coordination Number, ECoN, these via Mean Fictive Ionic Radii, MEFIR will be calculated and discussed. |
