Gadolinium (Gd)
Element 64 · Lanthanide · atomic mass 157.25 u · f-block, period 6
Electron shells: 2, 8, 18, 25, 9, 2
Gadolinium absorbs neutrons better than almost any other element and is strongly paramagnetic. Its compounds are injected as MRI contrast agents.
Gadolinium becomes magnetic when cold and loses it near room temperature — the basis of magnetic cooling.
- Atomic number
- 64
- Atomic mass
- 157.25 u
- Electron configuration
- [Xe] 6s² 4f⁷ 5d¹
- Group · period · block
- f-block · 6 · f
- Oxidation states
- +3
- Electronegativity
- 1.2 (Pauling)
- Melting point
- 1,313 °C
- Boiling point
- 3,273 °C
- Density
- 7.9 g/cm³
- State at 20 °C
- Solid
- Appearance
- Silvery-white metal
- Discovered
- Jean Charles Galissard de Marignac, 1880
64 protons, and 64 electrons when neutral
IUPAC standard atomic weight
Shown in the strip below the table
What Gadolinium is used for
- MRI contrast agents
- Nuclear reactor shielding and control
- Magnetic refrigeration research
- Phosphors and X-ray screens
Atomic structure of Gadolinium
A neutral gadolinium atom has 64 protons and 64 electrons. Its most common isotope carries about 93 neutrons, which is where the mass number 157 comes from. Change the neutron count and you have a different isotope of gadolinium; change the proton count and you have a different element entirely.
Those electrons fill shells from the inside out: 2, 8, 18, 25, 9, 2. In orbital notation that is [Xe] 6s² 4f⁷ 5d¹. As a f-block element its valence count is variable, which is why it can form compounds in several oxidation states.
3D electron orbitals
See where Gadolinium's electrons actually are — a cloud of 26,000 points sampled from the probability density |ψ|², not a cartoon of a lobe.
Where Gadolinium sits in the periodic table
Discovery and naming
Gadolinium was discovered by Jean Charles Galissard de Marignac in 1880. Its name comes from Johan Gadolin, Finnish chemist, which is also why its symbol (Gd) does not match its English name.
Keep exploring
Atomic weight from IUPAC/CIAAW; physical properties from PubChem (US National Library of Medicine). Values that have never been measured are shown as “not measured” rather than estimated.
Related Calculators
Frequently Asked Questions
What is the atomic mass of Gadolinium?
The standard atomic weight of Gadolinium is 157.25 u, as published by IUPAC's Commission on Isotopic Abundances and Atomic Weights.
How many protons, neutrons and electrons does Gadolinium have?
Gadolinium has 64 protons, because the atomic number is the proton count and that is what makes an atom Gadolinium at all. A neutral Gadolinium atom has the same number of electrons, 64. The neutron count varies by isotope; the most common one has about 93, since 157 − 64 = 93.
What is the electron configuration of Gadolinium?
The electron configuration of Gadolinium is [Xe] 6s² 4f⁷ 5d¹. Its electrons are arranged 2, 8, 18, 25, 9, 2 across 6 shells.
Is Gadolinium a metal?
Yes. Gadolinium is classified as a lanthanide, on the metallic side of the table.
What group and period is Gadolinium in?
Gadolinium sits in the f-block strip below the main table, in period 6, among the lanthanides. Elements in that strip are not given a group number in the standard 18-column layout.
What is the charge of Gadolinium?
Gadolinium most commonly forms a 3+ ion. Like most transition metals it has several accessible oxidation states, so the charge depends on the compound.
What is the melting point of Gadolinium?
Gadolinium melts at 1,313 °C and boils at 3,273 °C. That puts it in the solids at everyday temperatures.
What is Gadolinium used for?
MRI contrast agents, Nuclear reactor shielding and control, Magnetic refrigeration research, Phosphors and X-ray screens. Gadolinium absorbs neutrons better than almost any other element and is strongly paramagnetic.
Who discovered Gadolinium, and where does its name come from?
Gadolinium (Gd) was discovered by Jean Charles Galissard de Marignac in 1880. The name comes from Johan Gadolin, Finnish chemist.