About

Gadolinium is a silvery-white rare-earth metal that is ferromagnetic at low temperatures. Its compounds have exceptionally high magnetic moments, making them highly effective as intravenous contrast agents in MRI scans, enhancing the visibility of tumors and tissues. It also has the highest neutron-capture cross-section of any stable element, suggesting uses in nuclear shielding.

Atomic Properties

Atomic Number64

Atomic Weight157.25 u

Neutrons (common)94

Electron Configuration[Xe] 4f⁷ 5d¹ 6s²

Full Configuration1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f⁷ 5s² 5p⁶ 5d¹ 6s²

Electrons per Shell2, 8, 18, 25, 9, 2

Electronegativity1.2

Electron Affinity13.22 kJ/mol

Oxidation States+3

Covalent Radius169 pm

Ionic Radius93.8 pm

Periodic Table Position

Group3

Period6

BlockF

Chemical SeriesLanthanoids

Physical Properties

State at STPsolid

AppearanceSilvery-white metallic

Density at STP7.9 g/cm³

Crystal Structurehcp

Magnetic Orderingferromagnetic

Speed of Sound2,940 m/s

Poisson Ratio0.259

Thermal Properties

Melting Point1,585 K

Boiling Point3,546 K

Thermal Expansion0 1/K

Thermal Conductivity10.6 W/(m·K)

Specific Heat0.236 J/(g·K)

Molar Heat37.11 J/(mol·K)

Heat of Fusion10.05 kJ/mol

Heat of Vaporization301.3 kJ/mol

Abundance

In Earth's Crust6.2 ppm

In Ocean0 ppm

In Solar System0.262 ppm

In Universe0.002 ppm

Discovery

Discovered byJean Charles Galissard de Marignac

Discovery Year1,880

Occurrenceprimordial

CAS Number7440-54-2

Electron Configuration

Energy

↿⇂

↿

Isotopes of Gadolinium

Symbol ▲	Mass (u) ▲	Abundance ▲	Half-life ▲	Decay Mode ▲
¹⁵²Gd	151.919790	0.2%	108 Ty	Alpha Decay
¹⁵⁴Gd	153.920860	2.18%	Stable	Stable
¹⁵⁵Gd	154.922620	14.8%	Stable	Stable
¹⁵⁶Gd	155.922120	20.47%	Stable	Stable
¹⁵⁷Gd	156.923960	15.65%	Stable	Stable
¹⁵⁸Gd	157.924100	24.84%	Stable	Stable
¹⁶⁰Gd	159.927050	21.86%	Stable	Stable

Interactive Visualization

Explore the 3D Bohr model of Gadolinium in our interactive viewer.

View 3D Model of Gadolinium