Synthesis, structure and electrical properties of Sr2CuO2(CO3), an oxide carbonate related to perovskite
Abstract
The phase Sr2CuO2(CO3) occurs as an intermediate in the reaction between SrCO3 and CuO to form Sr2CuO3. The conditions of formation have been examined, and the structure determined from time-of-flight neutron powder diffraction [tetragonal, P4/mmm; a= 3.9033(2)Å, c= 7.4925(4)Å]. The structure consists of alternating layers of composition [CuO2]2– and [CO3]2– perpendicular to [001], separated by layers of Sr2+ cations. The carbonate groups are all oriented to have one C—O bond along [100] or [010], and two bonds at ca. 30° to [001]. No clear evidence for long-range ordering of the CO3 groups was found.