Neodymium(III) oxide

Neodymium(III) oxide
IUPAC name Neodymium(III) oxide
Other names Neodymium oxide, Neodymium sesquioxide
Identifiers
CAS number	1313-97-9 Y
Properties
Molecular formula	Nd2O3
Molar mass	336.48 g/mol
Appearance	light bluish gray hexagonal crystals
Density	7.24 g/cm3
Melting point	2233°C
Boiling point	3760°C[1]
Solubility in water	.0003 g/100 mL (75 °C)
Structure
Crystal structure	Hexagonal, hP5
Space group	P-3m1, No. 164
Thermochemistry
Std enthalpy of formation ΔfHo298	-1807.9 kJ·mol-1
Standard molar entropy So298	158.6 J·mol-1·K-1
Specific heat capacity, C	111.3 J·mol-1·K-1[1]
Related compounds
Other anions	Neodymium(II) chloride Neodymium(III) chloride
Other cations	Uranium(VI) oxide Praseodymium(III) oxide Promethium(III) oxide
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

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].

Uses

Neodymium(III) oxide is used to dope glass, including sunglasses, 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]. 7000 tonnes of neodymium(III) oxide are produced worldwide each year. Neodymium(III) oxide is also used as a polymerization catalyst^[4].

Reactions

Neodymium(III) oxide is formed when neodymium(III) nitride or neodymium(III) hydroxide is burned in air^[6].

References

1. ^ ^{a b c} Lide, David R. (1998), Handbook of Chemistry and Physics (87 ed.), Boca Raton, FL: CRC Press, pp. 471; 552, ISBN 0849305942 
2. ^ Brady, George Stuart; Clauser, Henry R.; Vaccari, John A. (2002), Materials Handbook (15 ed.), New York: McGraw-Hill Professional, pp. 779, ISBN 9780071360760, http://books.google.com/?id=vIhvSQLhhMEC&pg=PA779&dq=%22Neodymium+oxide%22, retrieved 2009-03-18 
3. ^ Eagleson, Mary (1994), Concise Encyclopedia of Chemistry, Springer, pp. 680, ISBN 9783110114515, http://books.google.com/?id=Owuv-c9L_IMC&pg=PA680&dq=%22Neodymium(III)+oxide%22, retrieved 2009-03-18 
4. ^ ^{a b} Emsley, John (2003), Nature's Building Blocks, Oxford University Press, pp. 268–9, ISBN 9780198503408, http://books.google.com/?id=j-Xu07p3cKwC&pg=PA268&dq=%22Neodymium+oxide%22, retrieved 2009-03-18 
5. ^ Bray, Charles (2001), Dictionary of Glass (2 ed.), University of Pennsylvania Press, pp. 103, ISBN 9780812236194, http://books.google.com/?id=KbZkxDyeG18C&pg=PA102&dq=%22Neodymium+oxide%22, retrieved 2009-03-18 
6. ^ Spencer, James Frederick (1919), The Metals of the Rare Earths, London: Longmans, Green, and Co, pp. 115, http://books.google.com/?id=W2zxN_FLQm8C&pg=PA115&dq=%22Neodymium+oxide%22, retrieved 2009-03-18