Chemical synthesis of α-cobalt hydroxide

Precipitation reactions using ammonia yield a novel cobalt hydroxide phase that is structurally and compositionally similar to α-nickel hydroxide. The use of other synthetic methods yields the well-known β-Co(OH)2. The slab composition, mode of anion inclusion, and thermal behavior of the hydroxides obtained by ammonia precipitation are similar to those of α-nickel hydroxide; however, the materials are poorly ordered. A DIFFaX simulation of the powder X-ray diffraction patterns offers the best visual match with the observed patterns for a 50% stacking disorder and a disc radius between 100 and 1000 Å.