60
144.24

Nd

Neodymium

Identification

CAS Number: 7440-00-8
Discovery Year: 1925
Discoverer: C.F. Aver von Welsbach
Discovery Location: Austria

Properties

Atomic Mass: 144.242 Density: 7.01 g/cm³
Crust Abundance: 41.5 mg/kg
Crystal Structure: HEX

Atomic Dimensions

Atomic Radius: 185 pm
Atomic Radius (Rahm): 284 pm
Covalent Radius: 200.99999999999997 pm
Van der Waals Radius: 239 pm
Atomic Volume: 20.6 cm³/mol
Lattice Constant: 3.66 Å

Electronic Structure

Electron Config: [Xe] 4f4 6s2
Block: f
Period: 6 Electronegativity: 1.14 Electron Affinity: 1.916 eV
Oxidation States: +3

Abundance & Geochemistry

Crust Abundance: 41.5 mg/kg
Sea Abundance: 0.0000028 mg/L
Geochemical Class: rare earth & related
Goldschmidt Class: litophile

About

Soft bright silvery metallic element, belongs to the lanthanoids. Seven natural isotopes, Nd-144 being the only radioactive one with a half-life of 10^10 to 10^15 years. Six artificial radioisotopes have been produced. The metal is used in glass works to color class a shade of violet-purple and make it dichroic. One of the more reactive rare-earth metals, quickly reacts with air. Used in some rare-earth alloys. Neodymium is used to color the glass used in welder's glasses. Neodymium is also used in very powerful, permanent magnets (Nd2Fe14B). Discovered by Carl F. Auer von Welsbach in Austria in 1885 by separating didymium into its elemental components Praseodymium and neodymium. The name comes from the Greek words 'neos didymos' which means 'new twin'. Neodymium should be considered highly toxic, however evidence would seem to show that it acts as little more than a skin and eye irritant. The dust however, presents a fire and explosion hazard.

Isotopes

Nd-142 142 27.15%
Nd-144 144 23.80%
Nd-146 146 17.19%
Nd-143 143 12.17%
Nd-145 145 8.29%
Nd-148 148 5.76%
Nd-150 150 5.64%