Gadolinium (Gd)
Lanthanide
Gadolinium has the strongest response to magnetic fields of any element at room temperature. Injected as a safe chelated compound, it sharpens millions of MRI scans; in reactors it devours neutrons.
Position on the periodic table
Atomic properties
| Atomic number | 64 |
|---|---|
| Atomic mass | 157.253 amu |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f7 5d1 |
| Noble gas shorthand | [Xe] 4f7 5d1 6s2 |
| Electrons per shell | 2, 8, 18, 25, 9, 2 |
| Valence electrons (outer shell) | 2 |
| Common oxidation states | +3 |
| Electronegativity (Pauling) | 1.2 |
| Covalent radius (approx.) | 196 pm |
| First ionization energy | 593.4 kJ/mol |
| Electron affinity | 13.2 kJ/mol |
Physical properties
| State at 25 °C | Solid |
|---|---|
| Density | 7.9 g/cm³ |
| Melting point | 1311.8 °C (1585 K) |
| Boiling point | 2999.8 °C (3273 K) |
| Appearance | silvery white |
| Radioactive | No |
| Origin | Occurs naturally |
Electron configuration of gadolinium
Gadolinium's ground-state electron configuration is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f7 5d1, usually shortened to [Xe] 4f7 5d1 6s2. Its electrons occupy 6 shells (2, 8, 18, 25, 9, 2), placing it in period 6 of the f-block. Explore it interactively in the electron configuration calculator.
Uses of gadolinium
- MRI contrast agents
- Neutron shielding and reactor emergency shutdown
- Magneto-optic data storage
- Green phosphors
Biological role: None; free gadolinium ions are toxic, so medical agents are tightly chelated.
Occurrence: From bastnäsite and monazite ores.
Common compounds of gadolinium
Gd2O3
Gadolinium(III) oxide
History and discovery
Discovered: 1880 — Jean Charles Galissard de Marignac. Name origin: From gadolinite, honouring Finnish chemist Johan Gadolin.
Jean Charles Galissard de Marignac detected gadolinium spectroscopically in 1880.
Safety notes
Free gadolinium is toxic — MRI contrast agents wrap it in stable chelates that pass through the body.
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Practice questions
Quick practice: Gadolinium
1. What is the chemical symbol of Gadolinium?
2. What is the atomic number of Gadolinium?
3. Which category does Gadolinium belong to?
4. What is the state of Gadolinium at room temperature?
5. Which period of the periodic table is Gadolinium in?
Gadolinium FAQs
What is the atomic number of gadolinium?
Gadolinium's atomic number is 64 — every gadolinium atom has 64 protons in its nucleus.
What is the symbol for gadolinium?
Gd. From gadolinite, honouring Finnish chemist Johan Gadolin.
Is gadolinium a metal, nonmetal, or metalloid?
Gadolinium is classified as a lanthanide.
What state is gadolinium at room temperature?
At about 25 °C, gadolinium is a solid. It melts at 1311.8 °C.
What is gadolinium used for?
Key uses include: mri contrast agents; neutron shielding and reactor emergency shutdown; magneto-optic data storage.
Related elements
Keep working with this element
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