64
Gd
Gadolinium
158
Gadolinium (Gd)
LanthanidePeriod 6f-block-block
Gadolinium is a chemical element with symbol Gd and atomic number 64. It is a silvery-white, malleable and ductile rare-earth metal. It is found in nature only in combined (salt) form.
Latin name: Gadolinium
Atomic Number
64
Atomic Mass
158 g/mol
Phase (STP)
Solid
Electron Config.
[Xe] 4f⁷ 5d¹ 6s²
General
SymbolGd
Atomic Number64
Atomic Mass158 g/mol
CategoryLanthanide
Period6
Blockf-block
Electron Configuration[Xe] 4f⁷ 5d¹ 6s²
Valence Electrons10
Coloursilvery-white metallic
Appearancesilvery white
CAS NumberCAS7440-54-2
Physical Properties
Phase (STP)Solid
Density7.9 g/cm³
Melting Point1311.85°C · 2393.33°F · 1585.00 K
Boiling Point3272.85°C · 5923.13°F · 3546.00 K
Atomic Properties
Atomic Radius237 pm
Electronegativity1.2 Pauling
Ionization Energy593 kJ/mol
Oxidation States+3
Ion ChargeGd3+
Thermodynamic
Molar Heat37.03 J/(mol·K)
Crystal Structure
Crystal Structurehexagonal close-packed
Mechanical Properties
Mohs Hardness2.5
Nuclear & Hazards
Half-lifestable (Gd-158)
Abundance
In Universe0.00003%
In Sun0.000025%
In Earth's Crust0.0520%
In Meteorites0.00009999999999999999%
Discovery & History
Discovery Year1880
Discovered ByJean Charles Galissard de Marignac
Country of DiscoverySwitzerland
Isotopes of Gadolinium
| Isotope | Abundance | Half-life | Decay |
|---|---|---|---|
| Gd-152 | 0.2% | 1.08 × 10¹⁴ years | α |
| Gd-154 | 2.18% | Stable | — |
| Gd-155 | 14.8% | Stable | — |
| Gd-156 | 20.47% | Stable | — |
| Gd-157 | 15.65% | Stable | — |
| Gd-158 | 24.84% | Stable | — |
| Gd-160 | 21.86% | Stable | — |