Structure and properties of SrCu(OH)4·H2O

Abstract

The structure of SrCu(OH)₄·H₂O has been determined from a single-crystal X-ray refinement and shown to contain isolated square-planar [Cu(OH)₄]^2– groups separated by strontium ions and hydrogen bonded to water molecules. ESR, IR and UV/VIS spectra are also reported for this compound and are consistent with the presence of discrete [Cu(OH)₄]^2– square planes. Thermal decomposition of this material proceeded by a complex multistage process via Sr₂(OH)₂Cu(OH)₄, through CuO and Sr(OH)₂, to Sr₂CuO₃ and CuO. Consideration of the structure of SrCu(OH)₄·H₂O shows that the relative orientation of the [Cu(OH)₄]^2– units is such that they do not crosslink to form infinite CuO₂ sheets.