Calculating core-level excitations and x-ray absorption spectra of medium-sized closed-shell molecules with the algebraic-diagrammatic construction scheme for the polarization propagator

• Verfasst von: Wenzel, Jan [VerfasserIn]
• Verfasst von: Wormit, Michael [VerfasserIn]
• Verfasst von: Dreuw, Andreas [VerfasserIn]
• Titel: Calculating core-level excitations and x-ray absorption spectra of medium-sized closed-shell molecules with the algebraic-diagrammatic construction scheme for the polarization propagator
• Verf.angabe: Jan Wenzel, Michael Wormit, and Andreas Dreuw
• Umfang: 16 S.
• Fussnoten: Gesehen am 12.12.2017
• Titel Quelle: Enthalten in: Journal of computational chemistry
• Jahr Quelle: 2014
• Band/Heft Quelle: 35(2014), 26, S. 1900-1915
• ISSN Quelle: 1096-987X
• DOI: doi:10.1002/jcc.23703
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1566315255

Abstract

Core-level excitations are generated by absorption of high-energy radiation such as X-rays. To describe these energetically high-lying excited states theoretically, we have implemented a variant of the algebraic-diagrammatic construction scheme of second-order ADC(2) by applying the core-valence separation (CVS) approximation to the ADC(2) working equations. Besides excitation energies, the CVS-ADC(2) method also provides access to properties of core-excited states, thereby allowing for the calculation of X-ray absorption spectra. To demonstrate the potential of our implementation of CVS-ADC(2), we have chosen medium-sized molecules as examples that have either biological importance or find application in organic electronics. The calculated results of CVS-ADC(2) are compared with standard TD-DFT/B3LYP values and experimental data. In particular, the extended variant, CVS-ADC(2)-x, provides the most accurate results, and the agreement between the calculated values and experiment is remarkable. © 2014 Wiley Periodicals, Inc.