Beschreibung:
<jats:title>2011</jats:title>
<jats:p>The crystal structure of [Co(NH<jats:sub>3</jats:sub>)<jats:sub>6</jats:sub>](ADC)(HADC) · 2H<jats:sub>2</jats:sub>O (1) (ADC<jats:sup>2-</jats:sup> =acetylenedicarboxylate) (P2<jats:sub>1</jats:sub>=n, Z = 4) was mistakenly described as containing the [Co(H<jats:sub>2</jats:sub>O)<jats:sub>6</jats:sub>]<jats:sup>3+</jats:sup> ion [I. Stein, U. Ruschewitz, Z. Naturforsch. , 66b, 471 - 478]. A revision is reported. While attempting to reproduce 1, we isolated phase-pure crystalline material of [Co(NH<jats:sub>3</jats:sub>)<jats:sub>6</jats:sub>]Cl<jats:sub>2</jats:sub>(HADC) · H<jats:sub>2</jats:sub>O (2), the crystal structure of which was also reported in the article above. Upon standing in the aqueous mother liquor at room temperature for several days, the needle-shaped crystals of 2disappear, while blockshaped crystals of the formerly unknown compound [Co(NH<jats:sub>3</jats:sub>)<jats:sub>6</jats:sub>](ADC)(HADC) (3) grow. Satellite peaks in the X-ray diffraction frames indicate that the crystal structure is incommensurately modulated. Dissolving crystals of 3 in water at elevated temperature leads to plate-shaped crystals of the new compound [Co(NH<jats:sub>3</jats:sub>)<jats:sub>6</jats:sub>]<jats:sub>2</jats:sub>(ADC)<jats:sub>3</jats:sub> · 3H<jats:sub>2</jats:sub>O (4) upon slow cooling to room temperature. Compounds 2- 4 were investigated by elemental analysis, powder X-ray diffraction and infrared spectroscopy. Structural characterization of 4 by single-crystal X-ray analysis was also achieved (P1̅ , Z = 2). Complex 1, however, could not be reproduced </jats:p>