Complex carbonates of copper(II)

Abstract

The visible absorption spectra for a copper(II) salt dissolved in (i) (NH 4) 2CO 3 and (ii) in a mixture of K 2CO 3 and KHCO 3 show absorption maxima at 650 nm for (i) and 690 and 720 nm for (ii). Methods for the preparations of (a) Na 3[Cu 2(CO 3) 3OH]. 4H 2O, (b) Rb[Cu 2(CO 3) 2(OH)]. 6H 2O, (c) K[CH 5N 3H][Cu(CO 3) 2]. H 2O, (d) K[Co(NH 3) 6] 3[Cu 2(CO 3) 4(OH)] 2 and (e) Na[Co(NH 3) 6] 3− [Cu 2(CO 3) 4(OH)] 2 are described, as well as new methods for the preparation of (f) Na 2[Cu(CO 3) 2]. 3H 2O. The (g) potassium compound, K[Cu 2(CO 3) 2(OH)], is found to be a dihydrate. Magnetic measurements for (a), (f) and (g) give values in the range 1·83-1·92 B.M. The TGA and i.r. data for the compounds are reported. The X-ray diffraction data for compounds (a) and (g) are listed.