Synthesis, crystal structure, and magnetic properties of quasi-one-dimensional oxides Ca3Co1+xMn1-xO6

Synthetic conditions and magnetic properties of quasi-one-dimensional mixed oxides Ca3Co1 + xMn1 - xO6 were investigated for x = 0, 0.25, and 1.0 (K4C dCl6 structure type, space group R(3) over barc, Z = 6). The crystal struct ure of Ca3CoMnO6 was refined using neutron diffraction analysis. The Co-O ( 2.140 Angstrom) and Mn-O (1.906 Angstrom) bond lengths give evidence that t he 3d elements in this compound exist in the form of the Co2+ and Mn4+ cati ons. In contrast to the Ca3Co2O6 ferromagnet (T-K = 24 K), the manganese-co ntaining phases are characterized by antiferromagnet interactions with the Neel temperatures of 18 K (x = 0.25) and 13 K (x = 0).