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| Names | |
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| Other names
niobium(II) oxide
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| Identifiers | |
3D model (JSmol)
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| ChemSpider | |
PubChem CID
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| Properties | |
| NbO | |
| Molar mass | 108.905 g/mol[1] |
| Appearance | grey solid[1] |
| Odor | odorless |
| Density | 7.30 g/cm3[1] |
| Melting point | 1,937 °C (3,519 °F; 2,210 K)[1] |
| Solubility | slightly soluble in HCl insoluble in nitric acid |
| Structure[2] | |
| Cubic, cP6 | |
| Pm3m, No. 221 | |
a = 0.4211 nm
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Formula units (Z)
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3 |
| Thermochemistry[3] | |
Heat capacity (C)
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41.3 J/(mol·K) |
Std molar
entropy (S |
48.1 J/(mol·K) |
Std enthalpy of
formation (ΔfH⦵298) |
−405.85 kJ/mol |
Gibbs free energy (ΔfG˚)
|
−378.6 kJ/mol |
| Hazards | |
| GHS pictograms | |
| GHS Signal word | Warning |
| HH315Script error: No such module "Preview warning".Category:GHS errors, HH319Script error: No such module "Preview warning".Category:GHS errors, HH335Script error: No such module "Preview warning".Category:GHS errors | |
| PP261Script error: No such module "Preview warning".Category:GHS errors, PP264Script error: No such module "Preview warning".Category:GHS errors, PP264+P265Script error: No such module "Preview warning".Category:GHS errors, PP271Script error: No such module "Preview warning".Category:GHS errors, PP280Script error: No such module "Preview warning".Category:GHS errors, PP302+P352Script error: No such module "Preview warning".Category:GHS errors, PP304+P340Script error: No such module "Preview warning".Category:GHS errors, PP305+P351+P338Script error: No such module "Preview warning".Category:GHS errors, PP319Script error: No such module "Preview warning".Category:GHS errors, PP321Script error: No such module "Preview warning".Category:GHS errors, PP332+P317Script error: No such module "Preview warning".Category:GHS errors, PP337+P317Script error: No such module "Preview warning".Category:GHS errors, PP362+P364Script error: No such module "Preview warning".Category:GHS errors, PP403+P233Script error: No such module "Preview warning".Category:GHS errors, PP405Script error: No such module "Preview warning".Category:GHS errors, PP501Script error: No such module "Preview warning".Category:GHS errors | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Niobium monoxide is the inorganic compound with the formula NbO. It is a grey solid with metallic conductivity.[1]
NbO adopts an unusual cubic structure, similar to the rock salt structure but with some missing atoms compared to it, so that both niobium and oxygen atoms have square planar coordination geometries. The niobium centers are arranged in octahedra, and there is a structural similarity to the octahedral niobium clusters in lower halides of niobium. In NbO the Nb–Nb bond length is 298 pm which compares to 285 pm in the metal.[2] One study of the bonding concludes that strong and nearly covalent bonds exist between the metal centers.[5]
It is a superconductor with a transition temperature of 1.38 K.[6] It is used in capacitors where a layer of Nb2O5 is formed around NbO grains as the dielectric.[7][8][9]
NbO can be prepared by reduction of Nb2O5 by hydrogen. More typically, it is prepared by comproportionation:[10]