Berlin 2024 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
MA: Fachverband Magnetismus
MA 19: Surface Magnetism
MA 19.11: Talk
Tuesday, March 19, 2024, 12:15–12:30, EB 407
Magnetic state of rare earth atoms on NaCl films — •María Blanco-Rey1,2,3, Fernando Delgado4, Andrés Arnau1,2,3, Marina Pivetta5, Stefano Rusponi5, and Harald Brune5 — 1Universidad del País Vasco UPV/EHU, Spain — 2Donostia International Physics Center DIPC, Spain — 3Centro de Física de Materiales MPC-CSIC-UPV/EHU, Spain — 4Universidad de La Laguna, Spain — 5École Polytechnique Fédérale de Lausanne EPFL, Switzerland
A combination of STM and XAS experiments shows that rare earth atoms on NaCl/Ag have 4fn and 4fn−1 electronic configurations depending on the adsorption site. The NaCl film thickness determines the preferred adsorption site, which in turn defines the occupation of the 5d shell. In this contribution we show that DFT calculations for Gd and Eu ad-atoms can mimic the energetics and electronic occupation of the 6s5d shells, predicting a 4fn−1 configuration for the rare earth as a Na substitutional, an adsorption geometry that is favorable for 2ML of NaCl only. For thicker films, defect formation is hindered and only 4fn species are allowed. As the rare earth atom becomes decoupled from the Ag substrate, there is a preference for adsorption sites with reduced coordination.
Keywords: Rare earth; DFT; Valency; Defects; XMCD