Lanthanoid Ion Color
Reference work entry
The lanthanoids (often designated Ln) are the 15 elements with atomic numbers 57 (lanthanum) to 71 (lutetium).
Colors, Electron Configurations, and Energy Levels
Most of the lanthanoid ions exhibit rather pale characteristic colors when introduced into transparent solids or in water solutions, the most important being the Ln 3+ state (Table 1). These colors arise from electronic transitions between the ionic ground state and energy levels derived from 4f electron configurations lying between 1.77 and 3.10 eV above it, giving absorption maxima in the visible wavelength range (700–400 nm). Of more practical importance is color produced when ions excited to higher energy levels fall back to these 4f-derived levels and thence to the ground state, giving rise to characteristic visible emission spectra, which are used in many applications including fluorescent printing inks used as...
- 1.Tilley, R.J.D.: Chapter 7. In: Colour and the Optical Properties of Materials, 2nd edn. Wiley, Chichester (2011)Google Scholar
- 2.Nassau, K.: Chapter 4. In: The Physics and Chemistry of Colour, 2nd edn. Wiley, New York (2001)Google Scholar
- 3.Huang, C.-H. (ed.): Rare Earth Coordination Chemistry. Wiley, Singapore (2010)Google Scholar
- 4.Linganna, K., Jayasankar, C.K.: Luminescence Spectroscopy of the Lanthanides, Scholars Press (2013)Google Scholar
- 5.Häninen, P., Härmä, H. (eds.): Lanthanide Luminescence. Springer, Heidelberg (2011)Google Scholar
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