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  • 1 C.S.I.C. Instituto de Ciencias de Materiales de Madrid Serrano 113 28006 Madrid Spain Serrano 113 28006 Madrid Spain
  • 2 Universidad de Oriente Departamento de Química Cumaná (Sucre) Venezuela Cumaná (Sucre) Venezuela
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Abstract  

The basic salt cobalt(II) hydroxide fluoride was obtained by partial hydrolysis of a 0.2M solution CoF2. Mixed Co(II)Cu(II) hydroxide fluorides with an isomorphic substitution of Co(II) by Cu(II) ions up to 20% were also prepared. XRD data obtained on these compounds indicate that they are single-phase compounds, their X-ray powder patterns being almost identical to the Co(OH)0.7F1.3 diagram, with Zn(OH)F-type structure. However, their stoichiometries are very close to Co1−xCux(OH)F (0≤x≤0.2). Thermal analysis studies carried out up to 1273 K in still air or under dynamic vacuum conditions show that in air CoO or a mixture of CoO and CuO is formed as final product. In vacuum, at high temperature, with a Ta heating surface, pure α-Co or a mixture of α-Co and Cu is formed at about 973 K.