Misplaced Pages

Holmium(III) chloride

Names
Other names Holmium trichloride Holmiumchlorid
Identifiers
CAS Number	10138-62-2 14914-84-2 (hexahydrate)
ECHA InfoCard	100.030.339
PubChem CID	24992
UNII	CAR334HOLD
CompTox Dashboard (EPA)	DTXSID0064967
Properties
Chemical formula	HoCl3
Molar mass	271.289 g/mol
Appearance	yellow crystals hygroscopic
Density	3.7 g/cm
Melting point	720 °C (1,328 °F; 993 K)
Boiling point	1,500 °C (2,730 °F; 1,770 K) (decomposes)
Solubility in water	dissolves
Structure
Crystal structure	Monoclinic, mS16
Space group	C12/m1, No. 12
Related compounds
Other anions	Holmium(III) oxide
Other cations	Dysprosium(III) chloride, Erbium(III) chloride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). N verify (what is  ?) Infobox references

Holmium(III) chloride is the inorganic compound with the formula HoCl₃. It is a common salt but is mainly used in research. It can be used to produce pure holmium. It exhibits the same color-changing behavior seen in holmium oxide, being a yellow in natural lighting and a bright pink color in fluorescent lighting.

Preparation

The most commonly used method to obtain holmium(III) chloride involves heating a mixture of holmium(III) oxide and ammonium chloride at 200-250 °C:

Ho₂O₃ + 6 NH₄Cl → 2 HoCl₃ + 6 NH₃ + 2 H₂O

The hexahydrate of holmium(III) chloride can be obtained by reaction between holmium and hydrochloric acid:

2 Ho + 6 HCl → 2 HoCl₃ + 3 H₂

It can also be prepared by the direct reaction between holmium and chlorine:

2 Ho + 3 Cl₂ → 2 HoCl₃

Properties

Holmium(III) chloride and its hexahydrate are light yellow solids in daylight that are soluble in water. The hexahydrate starts to release water of crystallization at 64 °C. Holmium(III) chloride has a monoclinic crystal structure analogous to that of aluminum(III) chloride. In the solid state it has the YCl₃ layer structure.

References

1. Lide, David R., ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, Florida: CRC Press. ISBN 0-8493-0487-3.
2. Emsley, John (2003). Nature's building blocks: an A-Z guide to the elements (Reprinted with corrections ed.). Oxford: Oxford Univ. Press. ISBN 978-0-19-850340-8.
3. ^ Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY.
4. Webelements: Holmium
5. Ans, Jan d'; Ans, Jan d' (1998). Elemente, anorganische Verbindungen und Materialien. Taschenbuch für Chemiker und Physiker / D'Ans (4., neubearb. u. rev. Aufl ed.). Ort nicht ermittelbar: Verlag nicht ermittelbar. ISBN 978-3-540-60035-0.
6. Wells A.F. (1984) Structural Inorganic Chemistry 5th edition Oxford. ISBN 0-19-855370-6

• Holmium compounds
• Chlorides
• Lanthanide halides