arXiv 0902.36972009-02-21cond-mat.mtrl-scicond-mat.str-el

The f-electron challenge: localized and itinerant states in lanthanide oxides united by GW@LDA+U

Hong Jiang, Ricardo I. Gomez-Abal, Patrick Rinke, Matthias Scheffler

备注：: 4 pages including 3 figures; related publications can be found at http://www.fhi-berlin.mpg.de/th/th.html
DOI：: 10.1103/PhysRevLett.102.126403

英文摘要：

Many-body perturbation theory in the GW approach is applied to lanthanide oxides, using the local-density approximation plus a Hubbard U correction (LDA+U) as the starting point. Good agreement between the G0W0 density of states and experimental spectra is observed for CeO2 and Ce2O3. Unlike the LDA+U method G0W0 exhibits only a weak dependence on U in a physically meaningful range of U values. For the whole lanthanide sesquioxide (Ln2O3) series G0W0@LDA+U reproduces the main features found for the optical experimental band gaps. The relative positions of the occupied and unoccupied f-states predicted by G0W0 confirm the experimental conjecture derived from phenomenological arguments.

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