Praseodymium

Praseodymium • Lanthanide Rare Earth

Primary XPS region: Pr3d
Overlapping regions: Cu2p
Binding energies of common chemical states:

Chemical state	Binding energy Pr3d_5/2
Pr metal	932 eV

Experimental information

Collect entire Pr3d region (up to 990eV), making sure both Pr3d_5/2 and Pr3d_3/2 components are acquired.

Interpretation of XPS spectra

There is direct overlap between Pr3d and Cu2p peaks.
- Although Pr3d/Cu2p peaks have strong overlap, Pr3d spin-orbit components have a 3:2 intensity ratio compared to a 2:1 ratio for Cu2p.
- Check for the weaker Cu3p peak at 75eV.
- Check the positions of Pr and Cu Auger peaks (primary Cu LMM peak at kinetic energy is 918eV, compared to primary Pr peak at kineitic energy is 690eV).

About this element

Symbol: Pr
Date of discovery: 1885
Name origin: Greek prasios and didymos
Appearance: unknown
Discoverer: C.F. Aver von Welsbach
Obtained from: salts

Melting point: 1208 K
Boiling point: 3400 K
Density[kg/m³]: 6640
Molar volume: 20.8 × 10^-6 m³/mol
Protons/Electrons: 59
Neutrons: 82
Shell structure: 2,8,18,21,8,2
Electron configuration: [Xe]6s24f3
Oxidation state: 3
Crystal structure: hexagonal

Praseodymium should be stored under a light mineral oil or sealed in plastic, as it will develop a green coating which, in return, exposes more metal to oxidation. First discovered in 1885 by German chemist C. F. Auer von Welsbach, praseodymium’s primary use is as an alloying agent combined with magnesium to create high-strength metals for aircraft engines. Praseodymium is also a necessary element for studio lighting and projector lights used in the motion picture industry. This element forms the core of carbon arc lights. Praseodymium gives glasses and enamels a yellowish color. The element has no known biological role.