Resolving the singlet excited states manifold of benzophenone by first-principles simulations and ultrafast spectroscopy
File(s)Manuscript_rev2.pdf (8.6 MB)
Accepted version
Author(s)
Type
Journal Article
Abstract
Accurate characterization of the high-lying excited state manifolds of organic molecules is of fundamental importance for the interpretation of the rich response detected in time-resolved nonlinear electronic spectroscopies. Here, we have characterized the singlet excited states manifold of benzophenone (BP), a versatile organic photoinitiator and a well-known DNA photosensitizer. Benchmarks of various multiconfigurational/multireference (RASSCF/PT2) and time-dependent density functional theory (TD-DFT) approaches allowed assignments of experimental linear absorption signals of BP in the ultraviolet (UV) region, with unprecedented characterization of ground state absorptions in the far UV. Experimental transient absorption spectra obtained by UV-Vis pump-probe spectroscopy at very short time-delays are shown to be directly comparable to theoretical estimates of excited state absorptions (from the low-lying nOπ* and ππ* singlet states) in the Franck-Condon region. Multireference computations provided reliable interpretation of the PP spectra, with TD-DFT results yielding a fair agreement as long as electronic transitions featuring double excitations contributions are not involved. These results lay the groundwork for further computational studies and interpretation of experimental nonlinear electronic spectra of benzophenone in more complex systems, such as BP/DNA adducts.
Date Issued
2018-05-08
Date Acceptance
2017-12-01
Citation
Journal of Chemical Theory and Computation, 2018, 14 (5), pp.2570-2585
ISSN
1549-9618
Publisher
American Chemical Society
Start Page
2570
End Page
2585
Journal / Book Title
Journal of Chemical Theory and Computation
Volume
14
Issue
5
Copyright Statement
© 2018 American Chemical Society. This document is the Accepted Manuscript version of a Published Work that appeared in final form in the Journal of Chemical Theory and Computation, after peer review and technical editing by the publisher. To access the final edited and published work see https://dx.doi.org/10.1021/acs.jctc.7b01208
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/29614854
Subjects
Science & Technology
Physical Sciences
Chemistry, Physical
Physics, Atomic, Molecular & Chemical
Chemistry
Physics
DENSITY-FUNCTIONAL THEORY
2-DIMENSIONAL ELECTRONIC SPECTROSCOPY
PRIMARY PHOTOISOMERIZATION EVENT
MOLECULAR-ORBITAL METHODS
ANO BASIS-SETS
WAVE-FUNCTIONS
PHOTOEXCITED BENZOPHENONE
DNA-PHOTOSENSITIZATION
OPTICAL SPECTROSCOPY
ABSORPTION-SPECTRA
0307 Theoretical And Computational Chemistry
Chemical Physics
Publication Status
Published
Coverage Spatial
United States
Date Publish Online
2018-04-03