Abstract
K2NiF4 type (Ca2-xNdx)CoO4 (1.0≤x≤1.3) was synthesized from calcium acetate, neodymium oxide, and cobalt acetate. The increase in the cell volume is explained by the difference in the ionic radius of the Ca and Nd ions. (Ca2-xNdx)CoO4 is the semiconductor and the electrical resistivity at room temperature increases with increasing x.