Names | |
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IUPAC name
Neodymium(III) oxide
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Other names
Neodymium oxide, Neodymium sesquioxide
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Identifiers | |
3D model (JSmol)
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ChemSpider | |
ECHA InfoCard | 100.013.832 |
EC Number |
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PubChem CID
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
Nd2O3 | |
Molar mass | 336.48 g/mol |
Appearance | light bluish gray hexagonal crystals |
Density | 7.24 g/cm3 |
Melting point | 2,233 °C (4,051 °F; 2,506 K) |
Boiling point | 3,760 °C (6,800 °F; 4,030 K)[1] |
.0003 g/100 mL (75 °C) | |
+10,200.0·10−6 cm3/mol | |
Structure | |
Hexagonal, hP5 | |
P-3m1, No. 164 | |
Thermochemistry | |
Heat capacity (C)
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111.3 J·mol−1·K−1[1] |
Std molar
entropy (S⦵298) |
158.6 J·mol−1·K−1 |
Std enthalpy of
formation (ΔfH⦵298) |
−1807.9 kJ·mol−1 |
Related compounds | |
Other anions
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Neodymium(II) chloride Neodymium(III) chloride |
Other cations
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Uranium(VI) oxide Praseodymium(III) oxide Promethium(III) oxide |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Neodymium(III) oxide or neodymium sesquioxide is the chemical compound composed of neodymium and oxygen with the formula Nd2O3. It forms very light grayish-blue hexagonal crystals.[1] The rare-earth mixture didymium, previously believed to be an element, partially consists of neodymium(III) oxide.[2]
Neodymium(III) oxide is used to dope glass, including sunglasses, to make solid-state lasers, and to color glasses and enamels.[3] Neodymium-doped glass turns purple due to the absorbance of yellow and green light, and is used in welding goggles.[4] Some neodymium-doped glass is dichroic; that is, it changes color depending on the lighting. One kind of glass named for the mineral alexandrite appears blue in sunlight and red in artificial light.[5] About 7000 tonnes of neodymium(III) oxide are produced worldwide each year. Neodymium(III) oxide is also used as a polymerization catalyst.[4]
Neodymium(III) oxide is formed when neodymium(III) nitride or neodymium(III) hydroxide is roasted in air.[6]
Neodymium(III) oxide has a low-temperature trigonal A form in space group P3m1.[7] This structure type is favoured by the early lanthanides.[8][9] At higher temperatures it adopts two other forms, the hexagonal H form in space group P63/mmc and the cubic X form in Im3m. The high-temperature forms exhibit crystallographic disorder.[10][11]
Packing | Neodymium coordination | Oxygen O1 coordination | Oxygen O2 coordination |
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A-M2O3 structure type | approximately capped octahedral | octahedral | approximately tetrahedral |