67HoHolmium164.930332[Xe] 4f¹¹ 6s²
lanthanide

Holmium

Holmium is a chemical element with symbol Ho and atomic number 67. Part of the lanthanide series, holmium is a rare earth element. Holmium was discovered by Swedish chemist Per Theodor Cleve.

Electronic structure

A stylized shell model. Electrons are quantum objects, not particles following these literal paths. Sizes and motion are illustrative.

Electrons by shell
Electron configuration
4f11
6s2

54 is the [Xe] core total across five shells.

Properties

At a glance

Atomic number
67
Atomic mass
164.930332 u
Phase
Solid
Density
8.79 g/cm³
Melting point
1,734 K
Boiling point
2,873 K
First ionization energy
581 kJ/mol
Electronegativity
1.23
Electron affinity
32.61 kJ/mol
Molar heat capacity
27.15 J/(mol·K)
Period
6
Appearance
silvery white

Conditions and isotopes affect measured properties. Some properties of short-lived elements are predicted. Electronegativity uses the Pauling scale.

Keep exploring

Explore the stories, imagery, and reference data in more depth. Properties with no value in the reference are marked unavailable.