67Ho164.9303 Da

Holmium

Relatively soft and malleable silvery-white metallic element, which is stable in dry air at room temperature. It oxidizes in moist air and at high temperatures. It belongs to the lanthanoids. A rare-earth metal, it is found in the minerals monazite and gadolinite. It possesses unusual magnetic properties. One natural isotope, Ho-165 exists, six radioisotopes exist, the most stable being Ho-163 with a half-life of 4570 years. Holmium is used in some metal alloys, it is also said to stimulate the metabolism. Discovered by Per Theodor Cleve and J.L. Soret in Switzerland in 1879. The name homium comes from the Greek word Holmia which means Sweden. While all holmium compounds should be considered highly toxic, initial evidence seems to indicate that they do not pose much danger. The metal's dust however, is a fire hazard.

Gallery

Ultrapure Holmium, 17 grams. Original size in cm: 1.5 x 2.5

Unknown authorUnknown author, CC BY 1.0 <https://creativecommons.org/licenses/by/1.0>, via Wikimedia Commons, source: https://images-of-elements.com/holmium.php

Bohr model of Holmium

Physical Propertiesmass · density · phase · crystal

Atomic Mass

164.9303Da

Density

8.8000g/cm³

Phase (STP)

Solid

Melting Point

1745.2K

Boiling Point

2973.2K

Molar Heat

0.1650J/(mol·K)

Crystal Structure

HEX

Lattice Constant

3.580Å

Atomic Radiiatomic · covalent · van der Waals

Atomic (Empirical)

175.00pm

Covalent

166.00pm

Van der Waals

230.00pm

Electronic Propertieselectronegativity · ionization · affinity

Electron Configuration

[Xe] 4f11 6s2

Electron Shells

2, 8, 18, 29, 8, 2

Electronegativity

1.23Pauling

Electron Affinity

1st Ionization Energy

6.0kJ/mol

Oxidation States

+3

Orbital DiagramAufbau · Hund's rule · Pauli exclusion

1s2
2s2
2p6
3s2
3p6
3d10
4s2
4p6
4d10
5s2
5p6
4f11
6s2

Full: 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f11 6s2Short: [Xe] 4f11 6s2

Ionization Energies (67 known)

1st6.0 kJ/mol2nd11.8 kJ/mol3rd22.8 kJ/mol4th42.5 kJ/mol5th63.9 kJ/mol6th95.0 kJ/mol7th112.0 kJ/mol8th129.0 kJ/mol9th155.0 kJ/mol10th173.0 kJ/mol11th197.0 kJ/mol12th229.0 kJ/mol13th263.0 kJ/mol14th284.0 kJ/mol15th305.0 kJ/mol16th340.0 kJ/mol17th373.0 kJ/mol18th408.0 kJ/mol19th441.0 kJ/mol20th475.0 kJ/mol21th510.0 kJ/mol22th715.0 kJ/mol23th755.0 kJ/mol24th797.0 kJ/mol25th842.0 kJ/mol26th885.0 kJ/mol27th929.0 kJ/mol28th985.0 kJ/mol29th1029.0 kJ/mol30th1077.0 kJ/mol31th1122.0 kJ/mol32th1300.0 kJ/mol33th1346.0 kJ/mol34th1395.0 kJ/mol35th1443.0 kJ/mol36th1545.0 kJ/mol37th1598.0 kJ/mol38th1719.0 kJ/mol39th1773.6 kJ/mol40th3018.0 kJ/mol41th3125.0 kJ/mol42th3238.0 kJ/mol43th3359.0 kJ/mol44th3476.0 kJ/mol45th3592.0 kJ/mol46th3760.0 kJ/mol47th3880.0 kJ/mol48th4009.0 kJ/mol49th4131.0 kJ/mol50th4469.0 kJ/mol51th4576.0 kJ/mol52th4693.0 kJ/mol53th4802.0 kJ/mol54th5135.0 kJ/mol55th5258.0 kJ/mol56th5494.0 kJ/mol57th5611.0 kJ/mol58th12495.0 kJ/mol59th12790.0 kJ/mol60th13116.0 kJ/mol61th13417.0 kJ/mol62th14639.0 kJ/mol63th14998.0 kJ/mol64th15448.0 kJ/mol65th15745.8 kJ/mol66th63772.4 kJ/mol67th65137.1 kJ/molSuccessive Ionization Energies

Emission Spectrumvisible range · characteristic spectral lines

410
405
416
Ho emission
380nm750nm
410.4 nm(100%)405.4 nm(70%)416.3 nm(50%)

Abundanceby mass

🌍Earth's Crust
1.3 ppm
🌊Ocean
2.2e-7 ppm
Universe
500.0 ppt
🧬Human Body

Log scale · ppm = parts per million by mass

Biological Role

No biological role

No known biological role.

Discovery

Discovered By

J.L. Soret

Named By

Year

1878

Nuclear Data

Known Isotopes

39

Stable Isotopes

1

Stable Mass Numbers

165

Natural isotopic abundance (IUPAC recommended values)

Isotopes of Ho39 known

NuclideZNMass (AMU)Half-lifeDecayAbundance
140Ho6773139.9685266.00 msp, β⁺, β⁺p8+
141Ho6774140.9631084.10 msp (1%), β⁺, β⁺p7/2-
142Ho6775141.960010400 msβ⁺ (1%), β⁺p, p (0%)7-
165Hostable6798164.930329Stablestable (1%)7/2-10000.0000%
176Ho67109175.957713Unknownβ⁻, β⁻n4+
177Ho67110176.961052Unknownβ⁻ (1%), n7/2-
178Ho67111177.965507Unknownβ⁻, β⁻n2+
Wikipedia →Data: Bowserinator · IAEA NDS · mendeleev