Gadolinium (Gd) is chemical element 64, a lanthanide in the f-block, period 6 (PubChem).
- Atomic number: 64
- Symbol: Gd
- Group: none (f-block)
- Period: 6
- Atomic mass: 157.25 u
- Electron configuration: [Xe]6s2 4f7 5d1
- Electronegativity (Pauling scale): 1.2
- Atomic radius (van der Waals): 237 pm
- Ionization energy: 6.150 eV
- Oxidation states: +3
- Standard state: Solid
- Melting point: 1586 K
- Boiling point: 3546 K
- Density: 7.90 g/cm³
- Chemical group: Lanthanide
- Year discovered: 1880