Dysprosium(III) chloride

Dysprosium(III) chloride

Names
IUPAC names Dysprosium(III) chloride Dysprosium trichloride
Identifiers
CAS Number	10025-74-8 N
3D model (Jmol)	Interactive image
ChemSpider	59592 Y
ECHA InfoCard	100.030.024
PubChem	66207
UNII	Q2A03W637H N
InChI InChI=1S/3ClH.Dy/h3*1H;/q;;;+3/p-3 Y Key: BOXVSFHSLKQLNZ-UHFFFAOYSA-K Y InChI=1/3ClH.Dy/h3*1H;/q;;;+3/p-3 Key: BOXVSFHSLKQLNZ-DFZHHIFOAK
SMILES Cl[Dy](Cl)Cl
Properties
Chemical formula	DyCl3
Molar mass	268.86 g/mol (anhydrous)
Appearance	white solid
Density	3.67 g/cm3, solid
Melting point	647 °C (1,197 °F; 920 K) (anhydrous)
Boiling point	1,530 °C (2,790 °F; 1,800 K)
Solubility in water	Soluble
Structure
Crystal structure	AlCl3 structure
Coordination geometry	Octahedral
Hazards
EU classification (DSD)	not listed
Flash point	Non-flammable
Related compounds
Other anions	Dysprosium(III) fluoride Dysprosium(III) bromide Dysprosium(III) iodide Dysprosium(III) oxide
Other cations	Terbium(III) chloride Dysprosium(II) chloride Holmium(III) chloride
Related compounds	Dysprosium(II) chloride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YN ?)
Infobox references

Dysprosium(III) chloride (DyCl₃), also known as dysprosium trichloride, is a compound of dysprosium and chlorine. It is a white to yellow solid which rapidly absorbs water on exposure to moist air to form a hexahydrate, DyCl₃.6H₂O. Simple rapid heating of the hydrate causes partial hydrolysis^[1] to an oxychloride, DyOCl.

Preparation and reactions

DyCl₃ is often prepared by the "ammonium chloride route," starting from either Dy₂O₃ or hydrated chloride or oxychloride.^[2][3] or DyCl₃·6H₂O.^[4] These methods produce (NH₄)₂[DyCl₅]:

10 NH₄Cl + Dy₂O₃ → 2 (NH₄)₂[DyCl₅] + 6 NH₃ + 3 H₂O

DyCl₃·6H₂O + 2 NH₄Cl → (NH₄)₂[DyCl₅] + 6 H₂O

The pentachloride decomposes thermally according to the following equation:

(NH₄)₂[DyCl₅] → 2 NH₄Cl + DyCl₃

The thermolysis reaction proceeds via the intermediacy of (NH₄)[Dy₂Cl₇].

Treating Dy₂O₃ with aqueous HCl produces hydrated chloride (DyCl₃·6H₂O). This salt cannot be rendered anhydrous by heating. Instead one obtains an oxychloride.

Dysprosium(III) chloride is a moderately strong Lewis acid, which ranks as "hard" according to the HSAB concept. Aqueous solutions of dysprosium chloride can be used to prepare other dysprosium(III) compounds, for example dysprosium(III) fluoride:

DyCl₃ + 3 NaF → DyF₃ + 3 NaCl

Uses

Dysprosium(III) chloride can be used as a starting point for the preparation of other dysprosium salts. Dysprosium metal is produced when a molten mixture of DyCl₃ in eutectic LiCl-KCl is electrolysed. The reduction occurs via Dy²⁺, at a tungsten cathode.^[5]

Precautions

Dysprosium compounds are believed to be of low to moderate toxicity, although their toxicity has not been investigated in detail.

References

1. ↑ F. T. Edelmann, P. Poremba, in: Synthetic Methods of Organometallic and Inorganic Chemistry, (W. A. Herrmann, ed.), Vol. 6, Georg Thieme Verlag, Stuttgart, 1997.
2. ↑ Meyer, G. (1989). "The Ammonium Chloride Route to Anhydrous Rare Earth Chlorides-The Example of YCl₃". Inorganic Syntheses. 25: 146–150. doi:10.1002/9780470132562.ch35. ISBN 978-0-470-13256-2. 
3. ↑ Edelmann, F. T.; Poremba, P. (1997). Herrmann, W. A. (ed.), ed. Synthetic Methods of Organometallic and Inorganic Chemistry. VI. Stuttgart: Georg Thieme Verlag. ISBN 3-13-103021-6. 
4. ↑ Taylor, M.D.; Carter, C.P. "Preparation of anhydrous lanthanide halides, especially iodides". Journal of Inorganic and Nuclear Chemistry. 24 (4): 387–391. doi:10.1016/0022-1902(62)80034-7. 
5. ↑ Y. Castrillejo, M. R. Bermejo, A. I. Barrado, R. Pardo, E. Barrado, A. M. Martinez, Electrochimica Acta, 50, 2047-2057 (2005).