Abstract
We analyze the core and valence transitions in chromium in a series of materials with a number of different ligands and including the oxidation states: Cr-II, Cr-III, Cr-IV, and Cr-VI. To study the core-to-core transitions we employ the CTM4XAS program and investigate the shapes, widths, intensities, and energy positions of the K beta(1,3) and K beta' lines in each oxidation state. The theoretical spectra are compared with experimental data obtained with synchrotron radiation. We found that the K beta(1,3) peak shifts to higher energy with increasing spin state. In addition, the widths of the K beta(1,3) peak increases as the oxidation state decreases, which we explain from the increased spread of the multiplet structures. In the K beta' structure the presence of two peaks in Cr-II, Cr-III, and Cr-IV is due to the large 3p3d exchange interaction. For the analysis of the valence transitions we utilize the DV-Xa method. We study the dependence of the relative intensities of the K beta" and K beta(2,5) structures on symmetry, bond length, and the effective number of 3d and 4p electrons in different chemical environments.
Original language | English |
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Pages (from-to) | 22202-22210 |
Number of pages | 9 |
Journal | Journal of Physical Chemistry C |
Volume | 118 |
Issue number | 38 |
DOIs | |
Publication status | Published - 29 Aug 2014 |
Funding
This work has been supported by the Brazilian Synchrotron Light Laboratory (LNLS). Dr. Torres Deluigi wish to especially thank Dr. Kazuo Taniguchi for having allowed her to access the DV-X alpha method, and Dr. Takeshi Mukoyama for having taught her to use the DV-X alpha method, and for his helpful and permanent and advice.
Keywords
- MOLECULAR-ORBITAL CALCULATION
- HIGH-RESOLUTION
- SPECTROSCOPY
- FLUORESCENCE
- ALPHA
- INTENSITY
- METALS
- ENERGY
- STATE
- LINES