Prediction of Excited-State Energies and Singlet–Triplet Gaps of Charge-Transfer States Using a Restricted Open-Shell Kohn–Sham Approach
Organic molecules with charge-transfer (CT) excited states are widely used in industry and are especially attractive as candidates for fabrication of energy efficient OLEDs, as they can harvest energy from nonradiative triplets by means of thermally activated delayed fluorescence (TADF). It is there...
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| Format: | Article |
| Language: | en_US |
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American Chemical Society (ACS)
2018
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| Online Access: | http://hdl.handle.net/1721.1/115097 https://orcid.org/0000-0003-2061-3237 https://orcid.org/0000-0001-7111-0176 |
| _version_ | 1811093363460407296 |
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| author | Hait, Diptarka Zhu, Tianyu McMahon, David Paul Van Voorhis, Troy |
| author2 | Massachusetts Institute of Technology. Department of Chemistry |
| author_facet | Massachusetts Institute of Technology. Department of Chemistry Hait, Diptarka Zhu, Tianyu McMahon, David Paul Van Voorhis, Troy |
| author_sort | Hait, Diptarka |
| collection | MIT |
| description | Organic molecules with charge-transfer (CT) excited states are widely used in industry and are especially attractive as candidates for fabrication of energy efficient OLEDs, as they can harvest energy from nonradiative triplets by means of thermally activated delayed fluorescence (TADF). It is therefore useful to have computational protocols for accurate estimation of their electronic spectra in order to screen candidate molecules for OLED applications. However, it is difficult to predict the photophysical properties of TADF molecules with LR-TDDFT, as semilocal LR-TDDFT is incapable of accurately modeling CT states. Herein, we study absorption energies, emission energies, zero–zero transition energies, and singlet–triplet gaps of TADF molecules using a restricted open-shell Kohn–Sham (ROKS) approach instead and discover that ROKS calculations with semilocal hybrid functionals are in good agreement with experiments—unlike TDDFT, which significantly underestimates energy gaps. We also propose a cheap computational protocol for studying excited states with large CT character that is found to give good agreement with experimental results without having to perform any excited-state geometry optimizations. |
| first_indexed | 2024-09-23T15:44:04Z |
| format | Article |
| id | mit-1721.1/115097 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T15:44:04Z |
| publishDate | 2018 |
| publisher | American Chemical Society (ACS) |
| record_format | dspace |
| spelling | mit-1721.1/1150972022-10-02T03:46:26Z Prediction of Excited-State Energies and Singlet–Triplet Gaps of Charge-Transfer States Using a Restricted Open-Shell Kohn–Sham Approach Hait, Diptarka Zhu, Tianyu McMahon, David Paul Van Voorhis, Troy Massachusetts Institute of Technology. Department of Chemistry Voorhis, Troy Van Hait, Diptarka Zhu, Tianyu McMahon, David Paul Van Voorhis, Troy Organic molecules with charge-transfer (CT) excited states are widely used in industry and are especially attractive as candidates for fabrication of energy efficient OLEDs, as they can harvest energy from nonradiative triplets by means of thermally activated delayed fluorescence (TADF). It is therefore useful to have computational protocols for accurate estimation of their electronic spectra in order to screen candidate molecules for OLED applications. However, it is difficult to predict the photophysical properties of TADF molecules with LR-TDDFT, as semilocal LR-TDDFT is incapable of accurately modeling CT states. Herein, we study absorption energies, emission energies, zero–zero transition energies, and singlet–triplet gaps of TADF molecules using a restricted open-shell Kohn–Sham (ROKS) approach instead and discover that ROKS calculations with semilocal hybrid functionals are in good agreement with experiments—unlike TDDFT, which significantly underestimates energy gaps. We also propose a cheap computational protocol for studying excited states with large CT character that is found to give good agreement with experimental results without having to perform any excited-state geometry optimizations. 2018-04-30T17:13:10Z 2018-04-30T17:13:10Z 2016-06 2016-04 Article http://purl.org/eprint/type/JournalArticle 1549-9618 1549-9626 http://hdl.handle.net/1721.1/115097 Hait, Diptarka et al. “Prediction of Excited-State Energies and Singlet–Triplet Gaps of Charge-Transfer States Using a Restricted Open-Shell Kohn–Sham Approach.” Journal of Chemical Theory and Computation 12, 7 (June 2016): 3353–3359 © 2016 American Chemical Society https://orcid.org/0000-0003-2061-3237 https://orcid.org/0000-0001-7111-0176 en_US https://pubs.acs.org/doi/10.1021/acs.jctc.6b00426 Journal of Chemical Theory and Computation Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Chemical Society (ACS) Prof. Van Voorhis via Erja Kajosalo |
| spellingShingle | Hait, Diptarka Zhu, Tianyu McMahon, David Paul Van Voorhis, Troy Prediction of Excited-State Energies and Singlet–Triplet Gaps of Charge-Transfer States Using a Restricted Open-Shell Kohn–Sham Approach |
| title | Prediction of Excited-State Energies and Singlet–Triplet Gaps of Charge-Transfer States Using a Restricted Open-Shell Kohn–Sham Approach |
| title_full | Prediction of Excited-State Energies and Singlet–Triplet Gaps of Charge-Transfer States Using a Restricted Open-Shell Kohn–Sham Approach |
| title_fullStr | Prediction of Excited-State Energies and Singlet–Triplet Gaps of Charge-Transfer States Using a Restricted Open-Shell Kohn–Sham Approach |
| title_full_unstemmed | Prediction of Excited-State Energies and Singlet–Triplet Gaps of Charge-Transfer States Using a Restricted Open-Shell Kohn–Sham Approach |
| title_short | Prediction of Excited-State Energies and Singlet–Triplet Gaps of Charge-Transfer States Using a Restricted Open-Shell Kohn–Sham Approach |
| title_sort | prediction of excited state energies and singlet triplet gaps of charge transfer states using a restricted open shell kohn sham approach |
| url | http://hdl.handle.net/1721.1/115097 https://orcid.org/0000-0003-2061-3237 https://orcid.org/0000-0001-7111-0176 |
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