Reinvestigation of Sr2 [Cu(OH)6]

Abstract

During an investigation of the SrO-CuO-P2O5-H 2O system, single crystals of distrontium hexa-hydroxido-cuprate(II), Sr2 [Cu(OH) 6], were obtained by the hydro-thermal method. The blue prismatic crystals of Sr2 [Cu(OH) 6] adopt the same structure type as Ba2 [Cu(OH) 6], Sr 2 [Zn(OH) 6] and Ba2 [Zn(OH) 6]. The Cu atoms, located at (0, 0, 1/2 ) (site symmetry ), form /mutually isolated and highly elongated Cu(OH) 6 octa-hedra, which are inter-connected to slightly distorted Sr(OH) 6 trigonal prisms, forming a layered structure. The location of H atoms from difference Fourier maps and their refinement allowed the precise determination of a three-dimensional hydrogen-bonding network in which all hy-drox-ide O atoms are involved. In addition, the hydrogen-bonding topologies in Sr2 [Cu(OH) 6] and other similar hexa-hydroxido-metallates with the general formulae M1[M2(OH) 6], M12 [M2(OH) 6] and M13 [M2(OH) 6] were analysed in detail.