Dysprosium(III) chloride (DyCl₃), also known as dysprosium trichloride, is a compound of

dysprosium Dysprosium is a chemical element; it has symbol Dy and atomic number 66. It is a rare-earth element in the lanthanide series with a metallic silver luster. Dysprosium is never found in nature as a free element, though, like other lanthanides, it ...

and

chlorine Chlorine is a chemical element; it has Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between ...

. It is a white to yellow solid which rapidly absorbs water on exposure to moist air to form a hexa

hydrate In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understo ...

, DyCl₃·6H₂O. Simple rapid heating of the hydrate causes partial

hydrolysis Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water ...

F. T. Edelmann, P. Poremba, in: ''Synthetic Methods of Organometallic and Inorganic Chemistry'', (W. A. Herrmann, ed.), Vol. 6, Georg Thieme Verlag, Stuttgart, 1997. to an oxychloride, DyOCl.

Preparation and reactions

DyCl₃ is often prepared by the "

ammonium chloride Ammonium chloride is an inorganic chemical compound with the chemical formula , also written as . It is an ammonium salt of hydrogen chloride. It consists of ammonium cations and chloride anions . It is a white crystalline salt (chemistry), sal ...

route", starting from either Dy₂O₃ or the hydrated chloride DyCl₃·6H₂O. These methods produce (NH₄)₂ yCl₅ :10 NH₄Cl + Dy₂O₃ → 2 (NH₄)₂ yCl₅ + 6 NH₃ + 3 H₂O :DyCl₃·6H₂O + ''2'' NH₄Cl → (NH₄)₂ yCl₅+ 6 H₂O The pentachloride decomposes thermally according to the following equation: :(NH₄)₂ yCl₅ → 2 NH₄Cl + DyCl₃ The thermolysis reaction proceeds via the intermediacy of (NH₄) y₂Cl₇ Treating Dy₂O₃ with aqueous HCl produces the hydrated chloride DyCl₃·6H₂O, which cannot be rendered anhydrous by heating. Instead one obtains an

oxychloride In chemistry, oxohalides or oxyhalides are a group of chemical compounds with the chemical formula , where X is a halogen, and A is an element different than O and X. Known oxohalides have fluorine (F), chlorine (Cl), bromine (Br), and/or iodine ( ...

: :DyCl₃ + H₂O → DyOCl + 2 HCl Dysprosium(III) chloride is a moderately strong

Lewis acid A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any ...

, which ranks as "hard" according to the

HSAB concept HSAB is an acronym for "hard and soft (Lewis) acids and bases". HSAB is widely used in chemistry for explaining the stability of compounds, reaction mechanisms and pathways. It assigns the terms 'hard' or 'soft', and 'acid' or 'base' to chemical ...

. 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

salt In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more formally called table salt. In the form of a natural crystalline mineral, salt is also known as r ...

s. Dysprosium metal is produced when a molten mixture of DyCl₃ in eutectic LiCl- KCl is electrolysed. The reduction occurs via Dy²⁺, at a

tungsten Tungsten (also called wolfram) is a chemical element; it has symbol W and atomic number 74. It is a metal found naturally on Earth almost exclusively in compounds with other elements. It was identified as a distinct element in 1781 and first ...

cathode A cathode is the electrode from which a conventional current leaves a polarized electrical device such as a lead-acid battery. This definition can be recalled by using the mnemonic ''CCD'' for ''Cathode Current Departs''. Conventional curren ...

.Y. Castrillejo, M. R. Bermejo, A. I. Barrado, R. Pardo, E. Barrado, A. M. Martinez, ''Electrochimica Acta'', 50, 2047-2057 (2005).

Precautions

Dysprosium Dysprosium is a chemical element; it has symbol Dy and atomic number 66. It is a rare-earth element in the lanthanide series with a metallic silver luster. Dysprosium is never found in nature as a free element, though, like other lanthanides, it ...

compounds are believed to be of low to moderate

toxicity Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacteria, bacterium, or plant, as well as the effect o ...

, although their toxicity has not been investigated in detail.

References

{{DEFAULTSORT:Dysprosium(Iii) Chloride Dysprosium compounds Chlorides Lanthanide halides