Rhodium • Transition Metal

Primary XPS region: Rh3d
Overlapping regions: Mg KLL
Binding energies of common chemical states:

Experimental Information

N/A

Interpretation of XPS spectra

• Rh3d region has well separated spin-orbit components (Δ_metal=4.7eV).
  
  • Coster-Kronig effect observed, broadening Rh3d3/2 component compared to Rh3d_5/2, and making Rh3d_3/2 component shorter than expected.
• Rh3d peaks have asymmetric peak shape for metal.
  
  • RhO₂ may also have asymmetric peak shapes in some crystalline phases[1].
    • [1] Y. Abe et al., Surface Science Spectra, Vol. 8, No. 2, 2001

About This Element

Symbol: Rh
Date of Discovery: 1803
Name Origin: Greek rhodon
Appearance: silver-white
Discoverer: William Wollaston
Obtained From: platinum ores

Melting Point: 2237 K
Boiling Point: 3968 K
Density[kg/m3]: 12450
Molar Volume: 8.28 × 10-6 m3/mol
Protons/Electrons: 45
Neutrons: 58
Shell Structure: 2,8,18,16,1
Electron Configuration: [Kr]4d85s1
Oxidation State: 2,3,4
Crystal Structure: cubic

This silvery-white hard transition metal belongs to the platinum group. It has high reflectance and is hard and durable. Rhodium is primarily used as an alloying agent with platinum and iridium to improve high temperature strength and oxidatlion resistance. These metal alloys are employed in furnace windings, electrical contacts, and high temperature resistance wires. As the pure metal, rhodium’s brilliance and resistance to tarnish makes it well suited for plating jewelry. This metal was discovered in 1803 by W. Wollaston and is named from the Greek origin “rhono,” meaning rose, after the rosy-colored solution yielded by its salts.