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Updated: Apr 14, 2026

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
Published on: February 10, 2020
Calculating singlet excited states: Comparison with fast time-resolved infrared spectroscopy of coumarins
Magnus W D Hanson-Heine1, Alisdair Wriglesworth1, Maliha Uroos1
1School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
Abstract:
In contrast to the ground state, the calculation of the infrared (IR) spectroscopy of molecular singlet excited states represents a substantial challenge. Here, we use the structural IR fingerprint of the singlet excited states of a range of coumarin dyes to assess the accuracy of density functional theory based methods for the calculation of excited state IR spectroscopy. It is shown that excited state Kohn-Sham density functional theory provides a high level of accuracy and represents an alternative approach to time-dependent density functional theory for simulating the IR spectroscopy of singlet excited states.
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