Change search
ReferencesLink to record
Permanent link

Direct link
Carbon X-ray absorption spectra of fluoroethenes and acetone: A study at the coupled cluster, density functional, and static-exchange levels of theory
Linköping University, Sweden.ORCID iD: 0000-0002-1191-4954
2013 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 138, no 12, 124311Article in journal (Refereed) Published
Abstract [en]

Near carbon K-edge X-ray absorption fine structure spectra of a series of fluorine-substituted ethenes and acetone have been studied using coupled cluster and density functional theory (DFT) polarization propagator methods, as well as the static-exchange (STEX) approach. With the complex polarization propagator (CPP) implemented in coupled cluster theory, relaxation effects following the excitation of core electrons are accounted for in terms of electron correlation, enabling a systematic convergence of these effects with respect to electron excitations in the cluster operator. Coupled cluster results have been used as benchmarks for the assessment of propagator methods in DFT as well as the state-specific static-exchange approach. Calculations on ethene and 1,1-difluoroethene illustrate the possibility of using nonrelativistic coupled cluster singles and doubles (CCSD) with additional effects of electron correlation and relativity added as scalar shifts in energetics. It has been demonstrated that CPP spectra obtained with coupled cluster singles and approximate doubles (CC2), CCSD, and DFT (with a Coulomb attenuated exchange-correlation functional) yield excellent predictions of chemical shifts for vinylfluoride, 1,1-difluoroethene, trifluoroethene, as well as good spectral features for acetone in the case of CCSD and DFT. Following this, CPP-DFT is considered to be a viable option for the calculation of X-ray absorption spectra of larger π-conjugated systems, and CC2 is deemed applicable for chemical shifts but not for studies of fine structure features. The CCSD method as well as the more approximate CC2 method are shown to yield spectral features relating to π-resonances in good agreement with experiment, not only for the aforementioned molecules but also for ethene, cis-1,2-difluoroethene, and tetrafluoroethene. The STEX approach is shown to underestimate π-peak separations due to spectral compressions, a characteristic which is inherent to this method.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2013. Vol. 138, no 12, 124311
Keyword [en]
Complex polarization propagator, Coupled-cluster singles, Coupled-cluster singles and doubles, Coupled-cluster theory, Density functional theories (DFT), Exchange-correlation functionals, X-ray absorption fine structure spectrum, X-ray absorption spectrum, Acetone, Carbon, Chemical shift, Cluster analysis, Density functional theory, Electron correlations, Ethylene, Organic polymers, Polarization, X ray absorption, Numerical methods, ethylene derivative, article, chemistry, quantum theory, X ray absorption spectroscopy, Ethylenes, X-Ray Absorption Spectroscopy
National Category
Theoretical Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-198738DOI: 10.1063/1.4795835ISI: 000316969500078PubMedID: 23556727ScopusID: 2-s2.0-84875795530OAI: oai:DiVA.org:kth-198738DiVA: diva2:1059083
Funder
Swedish Research Council, 621-2010-5014EU, FP7, Seventh Framework Programme, 254326
Note

QC 20170118

Available from: 2016-12-22 Created: 2016-12-21 Last updated: 2017-01-18Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMedScopus

Search in DiVA

By author/editor
Norman, Patrick
In the same journal
Journal of Chemical Physics
Theoretical Chemistry

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

ReferencesLink to record
Permanent link

Direct link