Dysprosium #
Orbitals and Energies #
Note – these are listed in BINDING ENERGY
Dy 3d ≈ 1293 eV
Dy 4s ≈ 400 eV
Dy 4p ≈ 300 eV
Dy 4d ≈ 154 eV
Dy 5s ≈ 63 eV
Dy 5p ≈ 26 eV
Dy 4f ≈ 4 eV
Common Overlaps for Dy 3d #
I 3p – Pr 3d – Bi 4s – Sb 3s – Mn LMM (Al Ka X-rays)
Theory and Background #
The rare earth metal dysprosium (Dy) is found in the lanthanide series and has the ground state electronic configuration [Xe] 4f10 6s2. Since the metallic state of lanthanides is of little use, their surface chemistry is not greatly explored and to date, the published data on heavier lanthanide elements are mostly limited to non-monochromatic sources (Ref. 3). Given that photoemission of low-lying 4d orbitals will result in a final state of the form 4d94fn, complex multiplet splitting is observed through the coupling of the 4d core-hole and the partly filled 4f shell and are excellent materials to understand the complex spectra resulting from this phenomenon.
The lanthanide series is a highly distinctive class of elements, with notable electrophilicity and magnetic and electronic properties. However, despite being an uncommon element presented to surface analysts, dysprosium finds many uses in alloys for technological applications such as laser materials (Ref. 4), infrared sources (Ref. 5), and to aid coercivity in neodymium-based magnets in harsh environments (Ref. 6).
Given that lanthanides are electropositive, they have a high affinity for oxygen and halides. Keeping them clean to record core-level spectra is difficult as noted previously (Ref. 7). Within this reference, the spectra for clean Dy are presented, which were obtained by light argon etching (20 s) between acquisitions.
Experimental Advice #
Dysprosium metal oxidises rapidly, even within a UHV chamber. In order to obtain metallic Dy spectra, a suitably sized fragment was wet polished to form a visually flat and smooth surface using isopropyl alcohol and SiC paper (grit size 7 μm). After polishing, the sample was again washed with isopropyl alcohol and dried under a stream of nitrogen. The dry sample was then attached to a conducting sample plate using copper clips. Initial survey scans (not shown) of the polished sample revealed small amounts of Si and Zn and significant amounts of carbon and oxygen. Spectra were collected after a 20 s etch after collection of the prior spectrum to minimize any oxidation. The 4f level exhibits a complex multiplet structure.
Data Analysis Guidance #
Dysprosium exhibits significant multiplet spitting and unknown samples should be collected with well known reference materials in order to correctly identify peak shapes ad structures.
References #
- Morgan, David J. “Core-level spectra of metallic lanthanides: Dysprosium (Dy).” Surface Science Spectra 30.2 (2023). Read it online here.
- Barreca, Davide, et al. “Nanostructured Dy2O3 films: an XPS investigation.” Surface Science Spectra 14.1 (2007): 52-59. Read it online here.
- Padalia, B. D., et al. “X-ray photoelectron core-level studies of the heavy rare-earth metals and their oxides.” Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences 354.1678 (1977): 269-290. Read it online here.
- Majewski, Matthew R., Robert I. Woodward, and Stuart D. Jackson. “Dysprosium mid‐infrared lasers: current status and future prospects.” Laser & Photonics Reviews 14.3 (2020): 1900195. Read it online here.
- Lide, David R., ed. CRC handbook of chemistry and physics. Vol. 85. CRC press, 2004. Read it online here.
- Fang, X., Y. Shi, and D. C. Jiles. “Modeling of magnetic properties of heat treated Dy-doped NdFeB particles bonded in isotropic and anisotropic arrangements.” IEEE transactions on magnetics 34.4 (1998): 1291-1293. Read it online here.
- Engelhard, Mark, and Don Baer. “Third row transition metals by X-ray photoelectron spectroscopy.” Surface Science Spectra 7.1 (2000): 1-68. Read it online here.
