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Holmium acetate

Holmium acetate
Names
Other names
Holmium(III) acetate
Identifiers
3D model (JSmol)
ECHA InfoCard 100.042.773 Edit this at Wikidata
  • InChI=1S/3C2H4O2.Ho/c3*1-2(3)4;/h3*1H3,(H,3,4);
    Key: NKWMPWXATGULJJ-UHFFFAOYSA-N
  • CC(=O)O.CC(=O)O.CC(=O)O.[Ho]
Properties
Ho(CH3COO)3
Appearance crystals
soluble
Related compounds
Other anions
 Holmium oxide
Holmium hydroxide
Other cations
 Dysprosium acetate
Erbium acetate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Holmium in acetic acid

Holmium acetate is the acetate salt of holmium, with a chemical formula of Ho(CH3COO)3[1] as well as at least one hydrate.

Preparation

Holmium acetate can be obtained by dissolving holmium oxide in hot acetic acid[2]

Ho2O3 + 6 CH3CO2H → 2 Ho(O2CH3)3 + 3 H2O

Dissolving holmium oxide in acetic acid at a pH of 4 will form the tetrahydrate of holmium acetate (Ho2(CH3COO)6·4H2O):[3] The anhydrous material can be obtained by heating the hydrated acetate in acetic acid.[1]

Physical properties and structure

Holmium acetate hemihepthydate decomposes at 105 °C, forming into a hemihydrate, further decomposing at 135 °C into an anhydride. Further adding heat will form Ho(OH)(CH3COO)2, HoO(CH3COO) then Ho2O2CO3, forming holmium oxide at 590 °C.[4]

According to X-ray crystallography, anhydrous holmium acetate is a coordination polymer. Each Ho(III) center is nine-coordinate, with two bidentate acetate ligands and the remaining sites occupied by oxygens provided by bridging acetate ligands. The lanthanum and praseodymium compounds are isostructural.[1] In a second polymorph, holmium acetate has 8-coordination.[2] A tetrahydrate has also been crystallized.[5]

Applications

Holmium acetate is used in the manufacture of ceramics, glass, phosphors, metal halide lamps, and as a dopant in garnet lasers. It is also used in nuclear reactors to keep the chain reaction in check.[6]

References

  1. ^ a b c Lossin, Adalbert; Meyer, Gerd (1994). "Pr(CH3COO)3, ein wasserfreies Selten-Erd-Acetat mit Netzwerkstruktur". Zeitschrift für Anorganische und Allgemeine Chemie. 620 (3). doi:10.1002/zaac.19946200306.
  2. ^ a b Lossin, Adalbert; Meyer, Gerd (1993). "Wasserfreie Selten-Erd-Acetate, M(CH3COO)3 (M = Sm-Lu, Y) mit Kettenstruktur. Kristallstrukturen von Lu(CH3COO)3 und Ho(CH3COO)3". Zeitschrift für Anorganische und Allgemeine Chemie. 619 (9). doi:10.1002/zaac.19936190917.
  3. ^ Anna Mondry, Krystyna Bukietyńska (1991-08-01). "Spectral intensities of holmium acetate single crystals". Inorganica Chimica Acta. 186 (1): 135–138. doi:10.1016/S0020-1693(00)87943-8. ISSN 0020-1693.
  4. ^ G. A. M. Hussein, B. A. A. Balboul, G. A. H. Mekhemer (2000-11-01). "Holmium oxide from holmium acetate, formation and characterization: thermoanalytical studies". Journal of Analytical and Applied Pyrolysis. 56 (2): 263–272. Bibcode:2000JAAP...56..263H. doi:10.1016/S0165-2370(00)00100-5. ISSN 0165-2370.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  5. ^ . doi:10.1107/S0567740879005987. {{cite journal}}: Cite journal requires |journal= (help); Missing or empty |title= (help)
  6. ^ "Holmium acetate". Retrieved 2014-01-01.

External reading

  • R. S. Kolat, J. E. Powell (1962-05-01). "Acetate Complexes of the Rare Earth and Several Transition Metal Ions". Inorganic Chemistry. 1 (2): 293–296. doi:10.1021/ic50002a019. ISSN 0020-1669.
Quelle: https://en.wikipedia.org/wiki/Holmium_acetate