Internal Conversion between Bright (1¹Bᵤ⁺) and Dark (2¹Ag⁻) States in s-trans-Butadiene and s-trans-Hexatriene
Abstract
Internal conversion (IC) between the two lowest singlet excited states, 1¹B_u⁺ and 2¹A_g⁻, of s-trans-butadiene and s-trans-hexatriene is investigated using a series of single- and multi- reference wave function and density functional theory (DFT) methodologies. Three independent types of the equation-of-motion coupled-cluster (EOMCC) theory capable of providing an accurate and balanced description of one- as well as two-electron transitions, abbreviated as δ-CR-EOMCC(2,3), DIP-EOMCC(4h2p){N₀}, and DEA-EOMCC(4p2h){N_u} or DEA-EOMCC(3p1h,4p2h){N_u}, consistently predict that the 1¹B_u⁺/2¹A_g⁻ crossing in both molecules occurs along the bond length alternation coordinate. However, the analogous 1¹B_u⁺ and 2¹A_g⁻ potentials obtained with some multireference approaches, such as CASSCF and MRCIS(D), as well as with the linear-response formulation of time-dependent DFT (TDDFT), do not cross. Hence, caution needs to be exercised when studying the low-lying singlet excited states of polyenes with conventional multiconfigurational methods and TDDFT. The multistate many-body perturbation theory methods, such as XMCQDPT2, do correctly reproduce the curve crossing. Among the simplest and least expensive computational methodologies, the DFT approaches that incorporate the contributions of doubly excited configurations, abbreviated as MRSF (mixed reference spin-flip) TDDFT and SSR(4,4), accurately reproduce our best EOMCC results. This is highly promising for nonadiabatic molecular dynamics simulations in larger systems.
Additional Information
© 2021 The Authors. Published by American Chemical Society. Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) Received 17 August 2021. Accepted 20 September 2021. Published online 30 September 2021. Published in issue 7 October 2021. This work was supported by the Samsung Science and Technology Foundations Grant SSTF-BA1701-12 (to C.H.C.) for fundamental theory developments, the NRF grants 2019H1D3A2A02102948 (to M.F.) and 2020R1A2C2008246 and 2020R1A5A1019141 (to C.H.C.) funded by the Ministry of Science and ICT for application of the developed methodologies, and the Chemical Sciences, Geosciences and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy Grant DE-FG02-01ER15228 (to P.P.). The authors declare no competing financial interest.Attached Files
Published - acs.jpclett.1c02707.pdf
Supplemental Material - jz1c02707_si_001.pdf
Supplemental Material - jz1c02707_si_002.pdf
Files
Additional details
- Alternative title
- Internal Conversion between Bright (11Bu+) and Dark (21Ag–) States in s-trans-Butadiene and s-trans-Hexatriene
- Alternative title
- Internal Conversion between Bright (1¹B_u⁺) and Dark (2¹A_g⁻) States in s-trans-Butadiene and s-trans-Hexatriene
- Eprint ID
- 111324
- Resolver ID
- CaltechAUTHORS:20211008-224623371
- SSTF-BA1701-12
- Samsung Science and Technology Foundation
- 2019H1D3A2A02102948
- National Research Foundation of Korea
- 2020R1A2C2008246
- National Research Foundation of Korea
- 2020R1A5A1019141
- National Research Foundation of Korea
- DE-FG02-01ER15228
- Department of Energy (DOE)
- Created
-
2021-10-12Created from EPrint's datestamp field
- Updated
-
2021-10-18Created from EPrint's last_modified field