Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 48, 2013
Previous Article Next Article

High-resolution molybdenum K-edge X-ray absorption spectroscopy analyzed with time-dependent density functional theory

Author affiliations

Abstract

X-ray absorption spectroscopy (XAS) is a widely used experimental technique capable of selectively probing the local structure around an absorbing atomic species in molecules and materials. When applied to heavy elements, however, the quantitative interpretation can be challenging due to the intrinsic spectral broadening arising from the decrease in the core–hole lifetime. In this work we have used high-energy resolution fluorescence detected XAS (HERFD-XAS) to investigate a series of molybdenum complexes. The sharper spectral features obtained by HERFD-XAS measurements enable a clear assignment of the features present in the pre-edge region. Time-dependent density functional theory (TDDFT) has been previously shown to predict K-pre-edge XAS spectra of first row transition metal compounds with a reasonable degree of accuracy. Here we extend this approach to molybdenum K-edge HERFD-XAS and present the necessary calibration. Modern pure and hybrid functionals are utilized and relativistic effects are accounted for using either the Zeroth Order Regular Approximation (ZORA) or the second order Douglas–Kroll–Hess (DKH2) scalar relativistic approximations. We have found that both the predicted energies and intensities are in excellent agreement with experiment, independent of the functional used. The model chosen to account for relativistic effects also has little impact on the calculated spectra. This study provides an important calibration set for future applications of molybdenum HERFD-XAS to complex catalytic systems.

Graphical abstract: High-resolution molybdenum K-edge X-ray absorption spectroscopy analyzed with time-dependent density functional theory

Back to tab navigation

Supplementary files

Article information


Submitted
25 Jul 2013
Accepted
14 Oct 2013
First published
07 Nov 2013

Phys. Chem. Chem. Phys., 2013,15, 20911-20920
Article type
Paper

High-resolution molybdenum K-edge X-ray absorption spectroscopy analyzed with time-dependent density functional theory

F. A. Lima, R. Bjornsson, T. Weyhermüller, P. Chandrasekaran, P. Glatzel, F. Neese and S. DeBeer, Phys. Chem. Chem. Phys., 2013, 15, 20911
DOI: 10.1039/C3CP53133C

Social activity

Search articles by author

Spotlight

Advertisements