Element Holmium

Holmium ElementPart of the lanthanide series, holmium is a rare-earth element.
Holmium was discovered by Swedish chemist Per Theodor Cleve. Its oxide was first isolated from rare-earth ores in 1878. The element’s name comes from Holmia, the Latin name for the city of Stockholm.
Holmium is a chemical element with the symbol Ho and atomic number 67.

Names and Identifiers

Chemical Formula:Ho
CAS:7440-60-0
Molecular Weight:164.930g/mol
EC Number :231-169-0
MDL Number:MFCD00011049
Color:silvery-white
Other Names:Olmio, Hólmio
PubChem CID:23988
IUPAC Name:Holmium
Inchl:InChI=1S/Ho
InChI Key:KJZYNXUDTRRSPN-UHFFFAOYSA-N
Canonical SMILES:[Ho]
ICSC Number:n/a

Physical & Chemical Properties

Phase:Solid
Density:8.79 g/cm³
Boiling Point:2873 K ​(2600 °C, ​4712 °F)
Melting Point:1734 K ​(1461 °C, ​2662 °F)
Molecular Formula:Ho
Flash Point:n/a
Exact Mass:164.930298
Symbol:Globally Harmonized System of Classification
Signal Word:Danger
Hazard Statements:H228
Precautionary Statements:n/a
Hazard Codes:F
Risk Phrases:11
Safety Phrases:n/a
RIDADR:n/a
WGK Germany:3
RTECS:n/a
Packaging Group:n/a
Hazard Class:n/a

Natural holmium contains one stable isotope, holmium-165. Some synthetic radioactive isotopes are known; the most stable one is holmium-163, with a half-life of 4570 years.

Naturally occurring isotopes

IsotopeMass/DaNatural abundance (atom %)Nuclear spin (I)Magnetic moment (μ/μN)
165Ho164.930319 (4)1007/24.173

Radiosotope data

IsotopeMass/DaHalf-lifeMode of decayNuclear spinNuclear magnetic moment
161Ho160.9278522.48 hEC to 161Dy7/24.25
162Ho161.92909215 mEC to 161Dy1
163Ho162.9287304570 yEC to 161Dy7/24.23
164Ho163.93023129 mEC to 161Dy; β to 164Er1
166Ho165.9322811.117 dβ to 166Er0
167Ho166.9331273.1 hβ to 167Er7/2

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