Holmium(III) sulfate

Holmium(III) sulfate
Names
	Other names Holmium sulfate;
Identifiers
CAS Number	15622-40-9; octahyddrate: 13473-57-9;
3D model (JSmol)	Interactive image; monohydrate: Interactive image; octahyddrate: Interactive image;
ChemSpider	146390; monohydrate: 21242007; octahyddrate: 32818082;
ECHA InfoCard	100.036.073
EC Number	239-697-3; octahyddrate: 630-442-5;
PubChem CID	167320; monohydrate: 25021756; octahyddrate: 57348038;
CompTox Dashboard (EPA)	DTXSID60890762 ; octahyddrate: DTXSID90721555;
	InChI InChI=1S/2Ho.3H2O4S/c;;31-5(2,3)4/h;;3(H2,1,2,3,4)/q2+3;;;/p-6 Key: MKPJADFELTTXAV-UHFFFAOYSA-H; monohydrate: InChI=1S/2Ho.3H2O4S.H2O/c;;31-5(2,3)4;/h;;3(H2,1,2,3,4);1H2/q2+3;;;;/p-6 Key: NTBVQHGZWAVKKD-UHFFFAOYSA-H; octahyddrate: InChI=1S/2Ho.3H2O4S.8H2O/c;;31-5(2,3)4;;;;;;;;/h;;3(H2,1,2,3,4);81H2/q2+3;;;;;;;;;;;/p-6 Key: BGUKVZHPVQVULL-UHFFFAOYSA-H;
	SMILES [O-]S(=O)(=O)[O-].[O-]S(=O)(=O)[O-].[O-]S(=O)(=O)[O-].[Ho+3].[Ho+3]; monohydrate: O.O=S(=O)([O-])[O-].O=S(=O)([O-])[O-].O=S(=O)([O-])[O-].[Ho+3].[Ho+3]; octahyddrate: O.O.O.O.O.O.O.O.O=S(=O)([O-])[O-].O=S(=O)([O-])[O-].O=S(=O)([O-])[O-].[Ho+3].[Ho+3];
Properties
Chemical formula	Ho2(SO4)3
Molar mass	618.03 g·mol−1
Appearance	Orange-yellow solid
Density	1.031 g/cm3
Solubility in water	45.56 g/L (25 °C); 14.77 g/L (95 °C)
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335
Precautionary statements	P261, P264, P264+P265, P271, P280, P302+P352, P304+P340, P305+P351+P338, P319, P321, P332+P317, P337+P317, P362+P364, P403+P233, P405, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Holmium(III) sulfate is a holmium compound with the chemical formula Ho₂(SO₄)₃. A hygroscopic orange-yellow octahydrate exists.^[1]^[4]

Preparation

Holmium(III) sulfate can be prepared by dissolving holmium(III) oxide in sulfuric acid:^[1]

Ho₂O₃ + 3 H₂SO₄ → Ho₂(SO₄)₃ + 3 H₂O

Adding triethylamine produces a 1-D amine templated holmium(III) sulfate material.^[5]

Reactions

Holmium(III) sulfate reacts with hydrogen sulfide to form holmium(III) sulfide at elevated temperatures.^[6]

Holmium(III) sulfate is a catalyst for orthohydrogen-parahydrogen conversion at cryogenic temperatures.^[7]

A holmium-silver sulfate (AgHo(SO₄)₂) can be synthesized from holmium(III) sulfate and silver sulfate:^[8]

Ag₂SO₄ + Ho₂(SO₄)₃ → 2AgHo(SO₄)₂

References

^ ^a ^b ^c Wickleder, Mathias S. (1998-10-01). "Synthesis, Crystal Structure, and Thermal Behavior of the Rare Earth Sulfates (H₅O₂)M(SO₄)₂ (M = Ho, Er, Y)". Chemistry of Materials. 10 (10): 3212–3216. doi:10.1021/cm980301w. ISSN 0897-4756.
^ ^a ^b ^c Judge, W. D.; Ng, K. L.; Moldoveanu, G. A.; Kolliopoulos, G.; Papangelakis, V. G.; Azimi, G. (2023-04-01). "Solubilities of heavy rare earth sulfates in water (gadolinium to lutetium) and H2SO4 solutions (dysprosium)". Hydrometallurgy. 218 106054: 3. doi:10.1016/j.hydromet.2023.106054. ISSN 0304-386X.
^ PubChem. "Sulfuric acid, holmium(3+) salt (3:2)". pubchem.ncbi.nlm.nih.gov. Retrieved 2026-01-22.
^ Perry, Dale L. (2016-04-19). Handbook of Inorganic Compounds. CRC Press. p. 198. ISBN 978-1-4398-1462-8.
^ Zhou, Wanli; Chen, Qi; Jiang, Ning; Meng, Xiang; Zhu, Dunru; Xu, Yan (2009). "Solvothermal synthesis, crystal structure and properties of a novel 1-D organic amine templated holmium sulfate". Inorganica Chimica Acta. 362 (9). Elsevier BV: 3299–3302. doi:10.1016/j.ica.2009.02.042. ISSN 0020-1693.
^ K. Wetzel (1963). "Lanthanum Sulfides". In G. Brauer (ed.). Handbook of Preparative Inorganic Chemistry, 2nd Ed. Vol. 2. NY, NY: Academic Press. p. 1153.
^ Davidson, Eric; Chang, Tiao-hsu; Chapin, Douglas S. (2002-05-01). "Surface Catalysis of the Orthohydrogen—Parahydrogen Conversion on Carbon-Supported Gadolinium and Holmium Sulfates at 77°K Using Ultrahigh-Vacuum Techniques". The Journal of Physical Chemistry. 70 (2): 347–351. doi:10.1021/j100874a005. Retrieved 2026-01-22.
^ Denisenko, Yuriy G.; Atuchin, Victor V.; Molokeev, Maxim S.; Wang, Naizheng; Jiang, Xingxing; Aleksandrovsky, Aleksandr S.; Krylov, Alexander S.; Oreshonkov, Aleksandr S.; Sedykh, Alexander E.; Volkova, Svetlana S.; Lin, Zheshuai; Andreev, Oleg V.; Müller-Buschbaum, Klaus (2021-06-20). "Negative thermal expansion in one-dimension of a new double sulfate AgHo(SO4)2 with isolated SO4 tetrahedra". Journal of Materials Science & Technology. 76: 111–121. doi:10.1016/j.jmst.2020.10.026. ISSN 1005-0302.

[wickleder-1] Wickleder, Mathias S. (1998-10-01). "Synthesis, Crystal Structure, and Thermal Behavior of the Rare Earth Sulfates (H₅O₂)M(SO₄)₂ (M = Ho, Er, Y)". Chemistry of Materials. 10 (10): 3212–3216. doi:10.1021/cm980301w. ISSN 0897-4756.

[judge-2] Judge, W. D.; Ng, K. L.; Moldoveanu, G. A.; Kolliopoulos, G.; Papangelakis, V. G.; Azimi, G. (2023-04-01). "Solubilities of heavy rare earth sulfates in water (gadolinium to lutetium) and H2SO4 solutions (dysprosium)". Hydrometallurgy. 218 106054: 3. doi:10.1016/j.hydromet.2023.106054. ISSN 0304-386X.

[3] PubChem. "Sulfuric acid, holmium(3+) salt (3:2)". pubchem.ncbi.nlm.nih.gov. Retrieved 2026-01-22.

[handbook-4] Perry, Dale L. (2016-04-19). Handbook of Inorganic Compounds. CRC Press. p. 198. ISBN 978-1-4398-1462-8.

[5] Zhou, Wanli; Chen, Qi; Jiang, Ning; Meng, Xiang; Zhu, Dunru; Xu, Yan (2009). "Solvothermal synthesis, crystal structure and properties of a novel 1-D organic amine templated holmium sulfate". Inorganica Chimica Acta. 362 (9). Elsevier BV: 3299–3302. doi:10.1016/j.ica.2009.02.042. ISSN 0020-1693.

[6] K. Wetzel (1963). "Lanthanum Sulfides". In G. Brauer (ed.). Handbook of Preparative Inorganic Chemistry, 2nd Ed. Vol. 2. NY, NY: Academic Press. p. 1153.

[7] Davidson, Eric; Chang, Tiao-hsu; Chapin, Douglas S. (2002-05-01). "Surface Catalysis of the Orthohydrogen—Parahydrogen Conversion on Carbon-Supported Gadolinium and Holmium Sulfates at 77°K Using Ultrahigh-Vacuum Techniques". The Journal of Physical Chemistry. 70 (2): 347–351. doi:10.1021/j100874a005. Retrieved 2026-01-22.

[8] Denisenko, Yuriy G.; Atuchin, Victor V.; Molokeev, Maxim S.; Wang, Naizheng; Jiang, Xingxing; Aleksandrovsky, Aleksandr S.; Krylov, Alexander S.; Oreshonkov, Aleksandr S.; Sedykh, Alexander E.; Volkova, Svetlana S.; Lin, Zheshuai; Andreev, Oleg V.; Müller-Buschbaum, Klaus (2021-06-20). "Negative thermal expansion in one-dimension of a new double sulfate AgHo(SO4)2 with isolated SO4 tetrahedra". Journal of Materials Science & Technology. 76: 111–121. doi:10.1016/j.jmst.2020.10.026. ISSN 1005-0302.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]