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Abstract SrZnSb2 has been prepared and characterized analytically and structurally. The compound crystallizes in the orthorhombic system with a = 2305 ± 5 pm, b = 437 ± 1 pm, c = 446 ± 1 pm, Pnma-D2h16. Zn- and Sb-atoms form distorted fourfold pyramids, connected by common edges in the basis to two-dimensional sheets. These sheets are separated by double layers of Sr-atoms in which further Sb-atoms are located building four-cornered networks.

Five new oxidpnictides have been prepared and structurally characterized. They crystallize in the tetragonal system, I4/mmm, with the following constants: Sr2Mn3As2O2: a = 416 ± 1 pm, c = 1884 ± 4 pm, c/a = 4.529, Ba2Mn3As2O2 : a = 424.8 ± 0 5 pm, c = 1977 ± 3 pm, c/a = 4.654, Sr2Mn3Sb2O2 : a = 426.2 ± 0.4 pm, c = 2011 ± 2 pm, c/a = 4.718, Ba2Mn3Sb2O2 : a = 436.7 ± 0.5 pm, c = 2078 ± 2 pm, c/a = 4.758, Sr2Mn3Bi2O2 : a = 428 ± 1 pm, c = 2055 ± 5 pm, c/a = 4.801. Mn- and As(Sb,Bi) atoms form tetragonal pyramids, connected by common edges in the basis to two-dimensional sheets. These sheets are separated by double layers of Sr atoms, in which Mn and O atoms are located forming MnO4 square plane nets.

Abstract The new compounds CaMn2As2, SrMn2As2 and BaMn2As2 have been prepared and their structures determined. The crystallographic data are (pm):CaMn2As2: P3̄m 1, a = 423 ± 1, c = 703 ± 1, c/a = 1.66 SrMri2As2:P3̄m 1, a = 429±1, c = 732 ± 1, c/a = 1.70BaMn2As2:I4/mmm, a = 415 ± 2, c = 1347 ± 2, c/a = 3.24

Abstract The new compound CaMnBi2 has been analytically and structurally characterized. CaMnBi2 crystallizes in the tetragonal system (a = 450 ± 1 pm, c = 1108 ± 2 pm, space group P4/nmm). Mn and Bi atoms form fourfold pyramids, connected by common edges in the basis to two-dimensional sheets. These sheets are separated by double layers of Ca atoms between which further Bi atoms are located forming squarenets. The structure is strongly related to that of SrZnSb2 which can be interpreted as a distorted variant of the new CaMnBi2 type.