A THEORETICAL AND EXPERIMENTAL INVESTIGATION OF MULTIPLET SPLITTING FOR CR and U SPECTRA GENERATED BY X-RAY PHOTOELECTRON SPECTROSCOPY.
EMSL Project ID
3058
Abstract
We propose a broad theoretical and experimental study of the 2p level multiplet structures for CrIII, CrIV, and CrV in a variety of bonding environments. Recent advances in theoretical calculations of multiplet splitting involving ab initio treatment of relativistic and many-body effects will be used to constrain factors influencing the multiplet structures for Cr ions. These factors include intrashell and intershell correlation, Madelung fields, and charge transfer. Our focus will be on the Cr 2p level because this is the strongest peak with the lowest chance for interference from other elements. This is an important consideration as our primary interest is interpreting XPS spectra for Cr sorbed in small amounts to surfaces of simple and complex oxides or silicates. CrIV and CrV are of interest because they are intermediate oxidation states between CrIII and CrVI and may be stabilized on surfaces during heterogeneous redox reactions involving CrIII or CrVI. Theoretical work will be performed by Prof. Paul Bagus at Texas A&M University and by Dr. J. R. Rustad at Pacific Northwest National Laboratory. The calculations will be correlated to and guided by experiments performed by Dr. Eugene S. Ilton at PNNL.Updated abstract Feb. 28, 2005
We propose a broad theoretical and experimental study of the 2p and 3p, and 4f level multiplet structures for the first row transition metals and U, respectively, in a variety of bonding environments. Recent advances in theoretical calculations of multiplet splitting involving ab initio treatment of relativistic and many-body effects will be used to constrain factors influencing the multiplet structures for the XPS of both transition metals and U. These factors include intrashell and intershell correlation, Madelung fields, the crystal field, covalency, and photo-induced charge transfer from the ligand to the metal. Our focus will be on the 2p and 4f levels because they are the strongest peaks with the lowest chance for interference from other elements. This is an important consideration as our primary interest is interpreting XPS spectra for metals sorbed in small amounts to surfaces of simple and complex oxides or silicates. Theoretical work will be performed by Prof. Paul Bagus at the University of North Texas. The calculations will be correlated to and guided by experiments performed by Dr. Eugene S. Ilton at PNNL.
Project Details
Project type
Exploratory Research
Start Date
2002-11-12
End Date
2005-10-24
Status
Closed
Released Data Link
Team
Principal Investigator
Related Publications
Bagus P, and ES Ilton. 2006. "Effects of Covalency on the p-Shell Photoemission of Transition Metals: MnO." Physical Review. B, Condensed Matter 73(15):155110.
Bagus P, C Woll, and ES Ilton. 2006. "A Definitive Analysis of the Rydberg and Valence Anti-bonding Character of States in the O K-edge of H2O." Chemical Physics Letters 428(1-3):207-212.
Bagus PS, ES Ilton, and JR Rustad. 2004. "Ligand-Field Effects for the 3p Photoelectron Spectra of Cr2O3." Physical Review. B, Condensed Matter and Materials Physics 69(20):205112.
Ilton ES, WA De Jong, and P Bagus. 2003. "Intra Atomic Many-Body Effects in P-shell Photoelectron Spectra of Cr3+ Ions." Physical Review. B, Condensed Matter and Materials Physics 68(12):125106.