64
Gd
Gadolinium
157.25
Atomic Number: 64
Atomic Weight: 157.25
Melting Point: 1586 K (1313°C or 2395°F)
Boiling Point: 3546 K (3273°C or 5923°F)
Density: 7.90 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Metal
Period Number: 6 Group Number: none Group Name: Lanthanide
What's in a name? Named for the mineral gadolinite which was named after Johan Gadolin, a Finnish chemist.
Say what? Gadolinium is pronounced as GAD-oh-LIN-ee-em.
History and Uses:
Spectroscopic evidence for the existence of gadolinium was first observed by the Swiss chemist Jean Charles Galissard de Marignac in the minerals didymia and gadolinite ((Ce, La, Nd, Y)2FeBe2Si2O10) in 1880. Today, gadolinium is primarily obtained from the minerals monazite ((Ce, La, Th, Nd, Y)PO4) and bastnasite ((Ce,La,Y)CO3F).
Gadolinium has the greatest ability to capture thermal neutrons of all known elements and can be used as control rods for nuclear reactors. Unfortunately, the two isotopes best suited for neutron capture, gadolinium-155 and gadolinium-157, are present in gadolinium in small amounts. As a result, gadolinium control rods quickly lose their effectiveness.
Gadolinium can be combined with yttrium to form garnets that have applications in microwave technology. Gadolinium can be alloyed with iron, chromium and other metals to improve their workability and their resistance to high temperatures and oxidation. Gadolinium compounds are used to make phosphors for color televisions.
Estimated Crustal Abundance: 6.2 milligrams per kilogram
Estimated Oceanic Abundance: 7×10-7 milligrams per liter
Number of Stable Isotopes: 5
Ionization Energy: 6.150 eV
Oxidation States: +3
Electron Shell Configuration:
1s2
2s2 2p6
3s2 3p6 3d10
4s2 4p6 4d10 4f7
5s2 5p6 5d1
6s2