Die Kristallstrukturbestimmung des monoklinen, basischen Kupfernitrates Cu4(NO3)2 (OH)6 II

TLDR: The complete crystal structure of monoclinic basic copper nitrate was determined by means of Patterson-, trial and error- and Fourier-methods as discussed by the authors, and the lattice constants, space group and atomic coordinates are tabulated on p. 383.

Abstract: The complete crystal structure of monoclinic basic copper nitrate was determined by means of Patterson-, trial and error- and Fourier-methods. The lattice constants, space group and atomic coordinates are tabulated on p. 383. The Cu atoms form a pseudohexagonal net (001) with CuCu = 3,03 resp. 3,17 A. Each CuI is surrounded by 2 OHI, 2 OHII and 2 OI (of NO3-groups) at the distances 2,00, 2,08 and 2,35 A (deformed octahedron); each CuII in an analogous way by 4 OHII, 1 OI and 1 OHI at 2,05, 2,18 and 2,27 A. The structure shows layers of octahedra (of the C6-type) CuX6/3 = CuX2 (X = OHI, OHII,OI). The distance OHIIOII is 2,46–2,60 A and is interpreted as a hydrogen bond OHII OII. The layers of octahedra are linked together by these H-bonds via the NO3-groups, which are nearly normal to the layer planes. Contrary to many layer structures this compound is optically positive, apparently a result of the position of the nitrate groups. The crystal structure is isotypical with the basic copper bromide.