User:Praseodymium-141/Holmium compounds

Holmium compounds are compounds formed by the element holmium (Ho). Holmium usually forms compounds in the +3 oxidation state, although compounds with holmium in the +2, +1 and 0 oxidation states are known.[1]

Oxides and chalcogenides

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Ho2O3, left: natural light, right: under a cold-cathode fluorescent lamp

Holmium(III) oxide is the only oxide of holmium. It changes its apparent color depending on the lighting conditions. In daylight, it has a tannish yellow color. Under trichromatic light, it appears orange red,[2] almost indistinguishable from the appearance of erbium oxide under the same lighting conditions.[3] The perceived color change is related to the sharp emission lines of trivalent holmium ions acting as red phosphors.[4]

Other chalcogenides are known for holmium. Holmium(III) sulfide has orange-yellow crystals in the monoclinic crystal system,[5] with the space group P21/m (No. 11).[6] Under high pressure, holmium(III) sulfide can form in the cubic and orthorhombic crystal systems.[7] It can be obtained by the reaction of holmium(III) oxide and hydrogen sulfide at 1325 °C.[8] Holmium(III) selenide is also known. It is antiferromagnetic below 6 K.[9]

Halides

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All four trihalides of holmium are known. Holmium(III) fluoride is a yellowish powder that can be produced by reacting holmium(III) oxide and ammonium fluoride, then crystallising it from the ammonium salt formed in solution.[10] Holmium(III) chloride can be prepared in a similar way, with ammonium chloride instead of ammonium fluoride.[11] It has the YCl3 layer structure in the solid state.[12] These compounds, as well as holmium(III) bromide and holmium(III) iodide, can be obtained by the direct reaction of the elements:[13]

2 Ho + 3 X2 → 2 HoX3

In addition, holmium(III) iodide can be obtained by the direct reaction of holmium and mercury(II) iodide, then removing the mercury by distillation.[14]

Organoholmium compounds

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Organoholmium compounds are very similar to those of the other lanthanides, as they all share an inability to undergo π backbonding. They are thus mostly restricted to the mostly ionic cyclopentadienides (isostructural with those of lanthanum) and the σ-bonded simple alkyls and aryls, some of which may be polymeric.[15]

References

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  1. ^ Yttrium and all lanthanides except Ce and Pm have been observed in the oxidation state 0 in bis(1,3,5-tri-t-butylbenzene) complexes, see Cloke, F. Geoffrey N. (1993). "Zero Oxidation State Compounds of Scandium, Yttrium, and the Lanthanides". Chem. Soc. Rev. 22: 17–24. doi:10.1039/CS9932200017. and Arnold, Polly L.; Petrukhina, Marina A.; Bochenkov, Vladimir E.; Shabatina, Tatyana I.; Zagorskii, Vyacheslav V.; Cloke (2003-12-15). "Arene complexation of Sm, Eu, Tm and Yb atoms: a variable temperature spectroscopic investigation". Journal of Organometallic Chemistry. 688 (1–2): 49–55. doi:10.1016/j.jorganchem.2003.08.028.
  2. ^ Ganjali, Mohammad Reza; Gupta, Vinod Kumar; Faridbod, Farnoush; Norouzi, Parviz (2016-02-25). Lanthanides Series Determination by Various Analytical Methods. Elsevier. p. 27. ISBN 978-0-12-420095-1.
  3. ^ Ganjali, Mohammad Reza; Gupta, Vinod Kumar; Faridbod, Farnoush; Norouzi, Parviz (2016-02-25). Lanthanides Series Determination by Various Analytical Methods. Elsevier. ISBN 978-0-12-420095-1.
  4. ^ Su, Yiguo; Li, Guangshe; Chen, Xiaobo; Liu, Junjie; Li, Liping (2008). "Hydrothermal Synthesis of GdVO4:Ho3+ Nanorods with a Novel White-light Emission". Chemistry Letters. 37 (7): 762–763. doi:10.1246/cl.2008.762.
  5. ^ Lide, David R. (2000). CRC Handbook of chemistry and physics: 2000-2001 a ready-reference book of chemical and physical data. Chemical rubber publishing company (81st ed.). Boca Raton New York Washington: CRC press. ISBN 978-0-8493-0481-1.
  6. ^ "Ho2S3: crystal structure, physical properties". Non-Tetrahedrally Bonded Binary Compounds II. Landolt-Börnstein - Group III Condensed Matter. Vol. 41D. 2000. pp. 1–3. doi:10.1007/10681735_623. ISBN 3-540-64966-2. Archived from the original on 2018-09-01. Retrieved 2021-06-22.
  7. ^ Tonkov, E. Yu (1998). Compounds and Alloys Under High Pressure A Handbook. CRC Press. p. 272. ISBN 978-90-5699-047-3.
  8. ^ G. Meyer; Lester R. Morss, eds. (1991). Synthesis of Lanthanide and Actinide Compounds. Kluwer Academic Publishers. pp. 329–335. ISBN 0792310187.
  9. ^ Bespyatov, M. A.; Musikhin, A. E.; Naumov, V. N.; Zelenina, L. N.; Chusova, T. P.; Nikolaev, R. E.; Naumov, N. G. (2018-03-01). "Low-temperature thermodynamic properties of holmium selenide (2:3)". The Journal of Chemical Thermodynamics. 118: 21–25. doi:10.1016/j.jct.2017.10.013. ISSN 0021-9614.
  10. ^ Riedel, moderne anorganische Chemie. Erwin Riedel, Christoph Janiak, Hans-Jürgen Meyer (4. Aufl ed.). Berlin: De Gruyter. 2012. ISBN 978-3-11-024900-2. OCLC 781540844.{{cite book}}: CS1 maint: others (link)
  11. ^ Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY.
  12. ^ Wells, A. F. (1984). Structural inorganic chemistry (5th ed.). Oxford [Oxfordshire]: Clarendon Press. ISBN 9780198553700. OCLC 8866491.
  13. ^ "Chemical reactions of Holmium". Webelements. Retrieved 2009-06-06.
  14. ^ Asprey, L. B.; Keenan, T. K.; Kruse, F. H. (1964). "Preparation and crystal data for lanthanide and actinide triiodides". Inorganic Chemistry. 3 (8): 1137–1141. doi:10.1021/ic50018a015.
  15. ^ Greenwood and Earnshaw, pp. 1248–9

Compounds Holmium compounds Category:Chemical compounds by element