Niobium monoxide, NbO

Niobium Oxides. The solubihty of oxygen in niobium obeys Henry s law to the solubiHty limit of the first oxide phase of 850—1300°C (123). The amount of oxygen in solution in niobium is 1.3 at. % at 850°C and nearly 2 at. % at 1000°C (124). Only three clearly defined anhydrous oxides of niobium have been obtained in bulk, ie, NbO, Nb02, and Nb20. Niobium monoxide, NbO, is obtained by hydrogen reduction of the pentoxide at... 

The unit cell of niobium monoxide NbO can be derived from the cubic unit cell of NaCl, by deleting the body-central Na+ (coordinate and the vertex... 

LiNbOj is prepared by the reaction of LijNb04 and NbO at 1050° as in Kumada et al. Unless otherwise specified, the reactants are heated to the reaction temperature in 1-2 h. The lithium niobium(V) oxide, Li3Nb04, is made as a white powder by heating a 3 1 molar ratio of Li2C03 (6.236 g, 84.41 mmol, Cerac, 99.8%) and Nb205 (7.478 g, 28.13 mmol, Cerac, 99.95%) in an alumina crucible at 900° for 3 days. Niobium monoxide, NbO, is obtained by heating a 3 1 molar ratio of Nb powder (5.118 g, 55.09 mmol, Cerac, 99.8%) and NbjO, (4.882 g, 18.37 mmol) in a fused-silica tube, sealed under vacuum, at 1100° for 3 days. 

For a reduction pressure of 10 4 atm, NbO and Nb2C react to form niobium and carbon monoxide at 1687 °C. When the carbon monoxide pressure is kept at 10-6 atm, the reaction resulting in the formation of the metal would occur, according to the diagram, at 1382 °C. 

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