1
|
Sanz García J, Maskri R, Mitrushchenkov A, Joubert-Doriol L. Optimizing Conical Intersections without Explicit Use of Non-Adiabatic Couplings. J Chem Theory Comput 2024; 20:5643-5654. [PMID: 38888629 DOI: 10.1021/acs.jctc.4c00326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
We present two alternative methods for optimizing minimum energy conical intersection (MECI) molecular geometries without knowledge of the derivative coupling (DC). These methods are based on the utilization of Lagrange multipliers: (i) one method uses an approximate calculation of the DC, while the other (ii) do not require the DC. Both methods use the fact that information on the DC is contained in the Hessian of the squared energy difference. Tests done on a set of small molecular systems, in comparison with other methods, show the ability of the proposed methods to optimize MECIs. Finally, we apply the methods to the furimamide molecule, to optimize and characterize its S1/S2 MECI, and to optimizing the S0/S1 MECI of the silver trimer.
Collapse
Affiliation(s)
- Juan Sanz García
- Univ Gustave Eiffel, Univ Paris Est Creteil, CNRS, UMR 8208, MSME, F-77454 Marne-la-Vallée, France
| | - Rosa Maskri
- Univ Gustave Eiffel, Univ Paris Est Creteil, CNRS, UMR 8208, MSME, F-77454 Marne-la-Vallée, France
| | - Alexander Mitrushchenkov
- Univ Gustave Eiffel, Univ Paris Est Creteil, CNRS, UMR 8208, MSME, F-77454 Marne-la-Vallée, France
| | - Loïc Joubert-Doriol
- Univ Gustave Eiffel, Univ Paris Est Creteil, CNRS, UMR 8208, MSME, F-77454 Marne-la-Vallée, France
| |
Collapse
|
2
|
Bai S, Zhang P, Beratan DN. Using Adiabatic Energy Splitting To Compute Dexter Energy Transfer Couplings. J Phys Chem A 2024. [PMID: 38968620 DOI: 10.1021/acs.jpca.3c08146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/07/2024]
Abstract
Dexter energy transfer and transport (DET) are of broad interest in energy science, and DET rates depend on electronic couplings between donor and acceptor species. DET couplings are challenging to compute since they originate from both one- and two-particle interactions, and the strength of this interaction drops approximately exponentially with donor-acceptor distances. Using adiabatic energy splitting to compute DET couplings has advantages because adiabatic states can be calculated directly using conventional quantum chemical methods. We describe a minimum energy splitting method to compute the DET coupling by altering molecular geometries to drive the systems into a T1/T2 energy quasi-degenerate-activated DA complex. We explore the accuracy of various quantum chemical approaches to calculate the Dexter couplings.
Collapse
Affiliation(s)
- Shuming Bai
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Peng Zhang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - David N Beratan
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
- Department of Biochemistry, Duke University, Durham, North Carolina 27710, United States
- Department of Physics, Duke University, Durham, North Carolina 27708, United States
| |
Collapse
|
3
|
Xu J, Hao J, Bu C, Meng Y, Xiao H, Zhang M, Li C. XMECP: Reaching State-of-the-Art MECP Optimization in Multiscale Complex Systems. J Chem Theory Comput 2024; 20:3590-3600. [PMID: 38651739 DOI: 10.1021/acs.jctc.4c00033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
The Python-based program, XMECP, is developed for realizing robust, efficient, and state-of-the-art minimum energy crossing point (MECP) optimization in multiscale complex systems. This article introduces the basic capabilities of the XMECP program by theoretically investigating the MECP mechanism of several example systems including (1) the photosensitization mechanism of benzophenone, (2) photoinduced proton-coupled electron transfer in the cytosine-guanine base pair in DNA, (3) the spin-flip process in oxygen activation catalyzed by an iron-containing 2-oxoglutarate-dependent oxygenase (Fe/2OGX), and (4) the photochemical pathway of flavoprotein adjusted by the intensity of an external electric field. MECPs related to multistate reaction and multistate reactivity in large-scale complex biochemical systems can be well-treated by workflows suggested by the XMECP program. The branching plane updating the MECP optimization algorithm is strongly recommended as it provides derivative coupling vector (DCV) with explicit calculation and can equivalently evaluate contributions from non-QM residues to DCV, which can be nonadiabatic coupling or spin-orbit coupling in different cases. In the discussed QM/MM examples, we also found that the influence on the QM region by DCV can occur through noncovalent interactions and decay with distance. In the example of DNA base pairs, the nonadiabatic coupling occurs across the π-π stacking structure formed in the double-helix system. In contrast to general intuition, in the example of Fe/2OGX, the central ferrous and oxygen part contribute little to the spin-orbit coupling; however, a nearby arginine residue, which is treated by molecular mechanics in the QM/MM method, contributes significantly via two hydrogen bonds formed with α-ketoglutarate (α-KG). This indicates that the arginine residue plays a significant role in oxygen activation, driving the initial triplet state toward the productive quintet state, which is more than the previous knowledge that the arginine residue can bind α-KG at the reaction site by hydrogen bonds.
Collapse
Affiliation(s)
- Jiawei Xu
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian, P. R. China
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jian Hao
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian, P. R. China
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Caijie Bu
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian, P. R. China
- College of Chemistry and Materials Science, Fujian Normal University, Fuzhou 350117, Fujian, P. R. China
| | - Yajie Meng
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian, P. R. China
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Han Xiao
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian, P. R. China
| | - Minyi Zhang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian, P. R. China
| | - Chunsen Li
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian, P. R. China
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
- Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, Xiamen University, Xiamen 361005, Fujian, P. R. China
| |
Collapse
|
4
|
Ziems KM, Kjellgren ER, Reinholdt P, Jensen PWK, Sauer SPA, Kongsted J, Coriani S. Which Options Exist for NISQ-Friendly Linear Response Formulations? J Chem Theory Comput 2024; 20:3551-3565. [PMID: 38662999 DOI: 10.1021/acs.jctc.3c01402] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2024]
Abstract
Linear response (LR) theory is a powerful tool in classic quantum chemistry crucial to understanding photoinduced processes in chemistry and biology. However, performing simulations for large systems and in the case of strong electron correlation remains challenging. Quantum computers are poised to facilitate the simulation of such systems, and recently, a quantum linear response formulation (qLR) was introduced [Kumar et al., J. Chem. Theory Comput. 2023, 19, 9136-9150]. To apply qLR to near-term quantum computers beyond a minimal basis set, we here introduce a resource-efficient qLR theory, using a truncated active-space version of the multiconfigurational self-consistent field LR ansatz. Therein, we investigate eight different near-term qLR formalisms that utilize novel operator transformations that allow the qLR equations to be performed on near-term hardware. Simulating excited state potential energy curves and absorption spectra for various test cases, we identify two promising candidates, dubbed "proj LRSD" and "all-proj LRSD".
Collapse
Affiliation(s)
- Karl Michael Ziems
- Department of Chemistry, Technical University of Denmark, Kemitorvet Building 207, DK-2800 Kongens Lyngby, Denmark
| | - Erik Rosendahl Kjellgren
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark
| | - Peter Reinholdt
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark
| | - Phillip W K Jensen
- Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark
| | - Stephan P A Sauer
- Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark
| | - Jacob Kongsted
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark
| | - Sonia Coriani
- Department of Chemistry, Technical University of Denmark, Kemitorvet Building 207, DK-2800 Kongens Lyngby, Denmark
| |
Collapse
|
5
|
Liu S, Lee Y, Chen L, Deng J, Ma T, Barbatti M, Bai S. Unexpected longer T 1 lifetime of 6-sulfur guanine than 6-selenium guanine: the solvent effect of hydrogen bonds to brake the triplet decay. Phys Chem Chem Phys 2024; 26:13965-13972. [PMID: 38669188 PMCID: PMC11078201 DOI: 10.1039/d4cp00875h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 04/14/2024] [Indexed: 04/28/2024]
Abstract
The decay of the T1 state to the ground state is an essential property of photosensitizers because it decides the lifetime of excited states and, thus, the time window for sensitization. The sulfur/selenium substitution of carbonyl groups can red-shift absorption spectra and enhance the triplet yield because of the large spin-orbit coupling, modifying nucleobases to potential photosensitizers for various applications. However, replacing sulfur with selenium will also cause a much shorter T1 lifetime. Experimental studies found that the triplet decay rate of 6-seleno guanine (6SeGua) is 835 times faster than that of 6-thio guanine (6tGua) in aqueous solution. In this work, we reveal the mechanism of the T1 decay difference between 6SeGua and 6tGua by computing the activation energy and spin-orbit coupling for rate calculation. The solvent effect of water is treated with explicit microsolvation and implicit solvent models. We find that the hydrogen bond between the sulfur atom of 6tGua and the water molecule can brake the triplet decay, which is weaker in 6SeGua. This difference is crucial to explain the relatively long T1 lifetime of 6tGua in an aqueous solution. This insight emphasizes the role of solvents in modulating the excited state dynamics and the efficiency of photosensitizers, particularly in aqueous environments.
Collapse
Affiliation(s)
- Shaoting Liu
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641, China.
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Yuhsuan Lee
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lingfang Chen
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingheng Deng
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Tongmei Ma
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641, China.
| | - Mario Barbatti
- Aix Marseille University, CNRS, ICR, 13397 Marseille, France.
- Institut Universitaire de France, Paris 75231, France
| | - Shuming Bai
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
6
|
Vandaele E, Mališ M, Luber S. The Role of Aqueous Solvation on the Intersystem Crossing of Nitrophenols. J Chem Theory Comput 2024; 20:3258-3272. [PMID: 38606908 PMCID: PMC11044273 DOI: 10.1021/acs.jctc.3c01400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 03/27/2024] [Accepted: 03/29/2024] [Indexed: 04/13/2024]
Abstract
The photochemistry of nitrophenols is a source of smog as nitrous acid is formed from their photolysis. Nevertheless, computational studies of the photochemistry of these widespread toxic molecules are scarce. In this work, the initial photodeactivation of ortho-nitrophenol and para-nitrophenol is modeled, both in gas phase and in aqueous solution to simulate atmospheric and aerosol environments. A large number of excited states, six for ortho-nitrophenol and 11 for para-nitrophenol, have been included and were all populated during the decay. Moreover, periodic time-dependent density functional theory (TDDFT) is used for both the explicitly included solvent and the solute. A comparison to periodic QM/MM (TDDFT/MM), with electrostatic embedding, is made, showing notable differences between the decays of solvated nitrophenols simulated with QM/MM and full (TD)DFT. A reduced intersystem crossing in aqueous solution could be observed thanks to the surface hopping approach using explicit, periodic TDDFT solvation including spin-orbit couplings.
Collapse
Affiliation(s)
- Eva Vandaele
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Momir Mališ
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Sandra Luber
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| |
Collapse
|
7
|
Arpa EM, Stafström S, Durbeej B. Photochemical formation of the elusive Dewar isomers of aromatic systems: why are substituted azaborines different? Phys Chem Chem Phys 2024; 26:11295-11305. [PMID: 38529645 DOI: 10.1039/d4cp00777h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/27/2024]
Abstract
Photochemical reactions enabling efficient transformation of aromatic systems into energetic but stable non-aromatic isomers have a long history in organic chemistry. One recently discovered reaction in this realm is that where derivatives of 1,2-azaborine, a compound isoelectronic with benzene in which two adjacent C atoms are replaced by B and N atoms, form the non-hexagon Dewar isomer. Here, we report quantum-chemical calculations that explain both why 1,2-azaborine is intrinsically more reactive toward Dewar formation than benzene, and how suitable substitutions at the B and N atoms are able to increase the corresponding quantum yield. We find that Dewar formation from 1,2-azaborine is favored by a pronounced driving force that benzene lacks, and that a large improvement in quantum yield arises when the reaction of substituted 1,2-azaborines proceeds without involvement of an intermediary ground-state species. Overall, we report new insights into making photochemical use of the Dewar isomers of aromatic compounds.
Collapse
Affiliation(s)
- Enrique M Arpa
- Division of Theoretical Chemistry, IFM, Linköping University, 58183 Linköping, Sweden.
- Institute of Organic Chemistry, RWTH Aachen University, 52056 Aachen, Germany.
| | - Sven Stafström
- Division of Theoretical Physics, IFM, Linköping University, 58183 Linköping, Sweden
| | - Bo Durbeej
- Division of Theoretical Chemistry, IFM, Linköping University, 58183 Linköping, Sweden.
| |
Collapse
|
8
|
Draženović J, Laconsay CJ, Došlić N, I-Chia Wu J, Basarić N. Excited-state antiaromaticity relief drives facile photoprotonation of carbons in aminobiphenyls. Chem Sci 2024; 15:5225-5237. [PMID: 38577382 PMCID: PMC10988595 DOI: 10.1039/d4sc00642a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Accepted: 03/02/2024] [Indexed: 04/06/2024] Open
Abstract
A combined computational and experimental study reveals that ortho-, meta- and para-aminobiphenyl isomers undergo distinctly different photochemical reactions involving proton transfer. Deuterium exchange experiments show that the ortho-isomer undergoes a facile photoprotonation at a carbon atom via excited-state intramolecular proton transfer (ESIPT). The meta-isomer undergoes water-assisted excited-state proton transfer (ESPT) and a photoredox reaction via proton-coupled electron transfer (PCET). The para-isomer undergoes a water-assisted ESPT reaction. All three reactions take place in the singlet excited-state, except for the photoredox process of the meta-isomer, which involves a triplet excited-state. Computations illustrate the important role of excited-state antiaromaticity relief in these photoreactions.
Collapse
Affiliation(s)
- Josip Draženović
- Department of Organic Chemistry and Biochemistry, Ruđer Bošković Institute Bijenička Cesta 54 10000 Zagreb Croatia
| | - Croix J Laconsay
- Department of Chemistry, University of Houston Houston TX 77204 USA
| | - Nađa Došlić
- Department of Physical Chemistry, Ruđer Bošković Institute Bijenička Cesta 54 10000 Zagreb Croatia
| | - Judy I-Chia Wu
- Department of Chemistry, University of Houston Houston TX 77204 USA
| | - Nikola Basarić
- Department of Organic Chemistry and Biochemistry, Ruđer Bošković Institute Bijenička Cesta 54 10000 Zagreb Croatia
| |
Collapse
|
9
|
Pracht P, Grimme S, Bannwarth C, Bohle F, Ehlert S, Feldmann G, Gorges J, Müller M, Neudecker T, Plett C, Spicher S, Steinbach P, Wesołowski PA, Zeller F. CREST-A program for the exploration of low-energy molecular chemical space. J Chem Phys 2024; 160:114110. [PMID: 38511658 DOI: 10.1063/5.0197592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Accepted: 02/29/2024] [Indexed: 03/22/2024] Open
Abstract
Conformer-rotamer sampling tool (CREST) is an open-source program for the efficient and automated exploration of molecular chemical space. Originally developed in Pracht et al. [Phys. Chem. Chem. Phys. 22, 7169 (2020)] as an automated driver for calculations at the extended tight-binding level (xTB), it offers a variety of molecular- and metadynamics simulations, geometry optimization, and molecular structure analysis capabilities. Implemented algorithms include automated procedures for conformational sampling, explicit solvation studies, the calculation of absolute molecular entropy, and the identification of molecular protonation and deprotonation sites. Calculations are set up to run concurrently, providing efficient single-node parallelization. CREST is designed to require minimal user input and comes with an implementation of the GFNn-xTB Hamiltonians and the GFN-FF force-field. Furthermore, interfaces to any quantum chemistry and force-field software can easily be created. In this article, we present recent developments in the CREST code and show a selection of applications for the most important features of the program. An important novelty is the refactored calculation backend, which provides significant speed-up for sampling of small or medium-sized drug molecules and allows for more sophisticated setups, for example, quantum mechanics/molecular mechanics and minimum energy crossing point calculations.
Collapse
Affiliation(s)
- Philipp Pracht
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany
| | - Christoph Bannwarth
- Institute for Physical Chemistry, RWTH Aachen University, Melatener Str. 20, 52056 Aachen, Germany
| | - Fabian Bohle
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany
| | - Sebastian Ehlert
- AI4Science, Microsoft Research, Evert van de Beekstraat 354, 1118 CZ Schiphol, The Netherlands
| | - Gereon Feldmann
- Institute for Physical Chemistry, RWTH Aachen University, Melatener Str. 20, 52056 Aachen, Germany
| | - Johannes Gorges
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany
| | - Marcel Müller
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany
| | - Tim Neudecker
- Institute for Physical and Theoretical Chemistry, University of Bremen, 28359 Bremen, Germany
| | - Christoph Plett
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany
| | | | - Pit Steinbach
- Institute for Physical Chemistry, RWTH Aachen University, Melatener Str. 20, 52056 Aachen, Germany
| | - Patryk A Wesołowski
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Felix Zeller
- Institute for Physical and Theoretical Chemistry, University of Bremen, 28359 Bremen, Germany
| |
Collapse
|
10
|
Calio PB, Hermes MR, Bao JJ, Galván IF, Lindh R, Truhlar DG, Gagliardi L. Minimum-Energy Conical Intersections by Compressed Multistate Pair-Density Functional Theory. J Phys Chem A 2024; 128:1698-1706. [PMID: 38407944 DOI: 10.1021/acs.jpca.3c07048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Compressed multistate pair-density functional theory (CMS-PDFT) is a multistate version of multiconfiguration pair-density functional theory that can capture the correct topology of coupled potential energy surfaces (PESs) around conical intersections. In this work, we develop interstate coupling vectors (ISCs) for CMS-PDFT in the OpenMolcas and PySCF/mrh electronic structure packages. Yet, the main focus of this work is using ISCs to calculate minimum-energy conical intersections (MECIs) by CMS-PDFT. This is performed using the projected constrained optimization method in OpenMolcas, which uses ISCs to restrain the iterations to the conical intersection seam. We optimize the S1/S0 MECIs for ethylene, butadiene, and benzene and show that CMS-PDFT gives smooth PESs in the vicinities of the MECIs. Furthermore, the CMS-PDFT MECIs are in good agreement with the MECI calculated by the more expensive XMS-CASPT2 method.
Collapse
Affiliation(s)
- Paul B Calio
- Department of Chemistry, Pritzker School of Molecular Engineering, James Franck Institute, Chicago Center for Theoretical Chemistry, The University of Chicago, Chicago, Illinois 60637-1403, United States
| | - Matthew R Hermes
- Department of Chemistry, Pritzker School of Molecular Engineering, James Franck Institute, Chicago Center for Theoretical Chemistry, The University of Chicago, Chicago, Illinois 60637-1403, United States
| | - Jie J Bao
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | | | - Roland Lindh
- Department of Chemistry-BMC, Uppsala University, Uppsala 75123, Sweden
| | - Donald G Truhlar
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Laura Gagliardi
- Department of Chemistry, Pritzker School of Molecular Engineering, James Franck Institute, Chicago Center for Theoretical Chemistry, The University of Chicago, Chicago, Illinois 60637-1403, United States
- Argonne National Laboratory, Lemont, Illinois 60439-4801, United States
| |
Collapse
|
11
|
Morreale D, Persico M. Topology of Conical Intersection Seams and the Geometric Phase. J Phys Chem A 2024; 128:1707-1714. [PMID: 38408203 DOI: 10.1021/acs.jpca.3c07042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
In this paper, we demonstrate two topological properties of crossing seams, that is, the sets of points in the N-dimensional space of nuclear coordinates where two electronic eigenstates are degenerate. We shall examine the typical case of states of the same spin with accidental degeneracies, whereby the crossing seam is of dimension N - 2. The first property we demonstrate is that a crossing seam has no boundary, therefore, it must either extend asymptotically to infinite values of one or more coordinates or wrap on itself. The second property is that two (or more) crossing seams can intersect each other but in such a way that neither of them ends at the intersection. When N = 3, the crossing seam is a line in a 3D space; this is so in triatomic molecules but also in reduced dimensionality treatments of larger polyatomics. The above-mentioned rules then mean that the crossing seam is a line of infinite length or a closed loop and can split into three branches but not in two. The example of the first two excited 1A' states of H2Cl+ illustrates these rules and shows their usefulness for computational search and characterization of crossing seams.
Collapse
Affiliation(s)
- Daniel Morreale
- Department of Chemistry and Industrial Chemistry, University of Pisa, v. G. Moruzzi 13, Pisa 56126, Italy
| | - Maurizio Persico
- Department of Chemistry and Industrial Chemistry, University of Pisa, v. G. Moruzzi 13, Pisa 56126, Italy
| |
Collapse
|
12
|
Gate G, Williams A, Boldissar S, Šponer J, Szabla R, de Vries M. The tautomer-specific excited state dynamics of 2,6-diaminopurine using resonance-enhanced multiphoton ionization and quantum chemical calculations. Photochem Photobiol 2024; 100:404-418. [PMID: 38124372 DOI: 10.1111/php.13897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 10/25/2023] [Accepted: 11/14/2023] [Indexed: 12/23/2023]
Abstract
2,6-Diaminopurine (2,6-dAP) is an alternative nucleobase that potentially played a role in prebiotic chemistry. We studied its excited state dynamics in the gas phase by REMPI, IR-UV hole burning, and ps pump-probe spectroscopy and performed quantum chemical calculations at the SCS-ADC(2) level of theory to interpret the experimental results. We found the 9H tautomer to have a small barrier to ultrafast relaxation via puckering of its 6-membered ring. The 7H tautomer has a larger barrier to reach a conical intersection and also has a sizable triplet yield. These results are discussed relative to other purines, for which 9H tautomerization appears to be more photostable than 7H and homosubstituted purines appear to be less photostable than heterosubstituted or singly substituted purines.
Collapse
Affiliation(s)
- Gregory Gate
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, USA
| | - Ann Williams
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, USA
| | - Samuel Boldissar
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, USA
| | - Jiří Šponer
- Institute of Biophysics of the Czech Academy of Sciences, Brno, Czech Republic
- Regional Centre of Advanced Technologies and Materials, Czech Advanced Technology and Research Institute (CATRIN), Palacky University Olomouc, Olomouc-Holice, Czech Republic
| | - Rafal Szabla
- Institute of Advanced Materials, Faculty of Chemistry, Wrocław University of Science and Technology, Wrocław, Poland
| | - Mattanjah de Vries
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, USA
| |
Collapse
|
13
|
Jankowska J, Sobolewski AL. Photo-oxidation of methanol in complexes with pyrido[2,3- b]pyrazine: a nonadiabatic molecular dynamics study. Phys Chem Chem Phys 2024; 26:5296-5302. [PMID: 38265828 DOI: 10.1039/d3cp04148d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Excited-state Proton-Coupled Electron Transfer (PCET) constitutes a key step in the photo-oxidation of small, electron-rich systems possessing acidic hydrogen atoms, such as water or alcohols, which can play a vital role in green hydrogen production. In this contribution, we employ ab initio quantum-chemical methods and on-the-fly nonadiabatic molecular dynamics simulations to study the mechanism and the photodynamics of PCET in 1 : 1 pyrido[2,3-b]pyrazine complexes with methanol. We find the process to be ultrafast and efficient when the intramolecular hydrogen bond is formed with one of the β-positioned nitrogen atoms. The complex exhibiting a hydrogen bond with an isolated nitrogen site, on the contrary, shows much lower reactivity. We explain this effect with the stabilization of the reactive ππ* charge-transfer electronic state in the former case.
Collapse
Affiliation(s)
- Joanna Jankowska
- Faculty of Chemistry, University of Warsaw, Pasteura 1, Warsaw 02-093, Poland.
| | - Andrzej L Sobolewski
- Institute of Physics, Polish Academy of Sciences, al. Lotników 32/46, Warsaw 02-668, Poland
| |
Collapse
|
14
|
Vandaele E, Mališ M, Luber S. A Local Diabatisation Method for Two-State Adiabatic Conical Intersections. J Chem Theory Comput 2024; 20:856-872. [PMID: 38174710 DOI: 10.1021/acs.jctc.3c01008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
A methodology to locally characterize conical intersections (CIs) between two adiabatic electronic states for which no nonadiabatic coupling (NAC) vectors are available is presented. Based on the Hessian and gradient at the CI, the branching space coordinates are identified. The potential energy surface around the CI in the branching space is expressed in the diabatic representation, from which the NAC vectors can be calculated in a wave-function-free, energy-based approach. To demonstrate the universality of the developed methodology, the minimum-energy CI (MECI) between the first (S1) and second (S2) singlet excited states of formamide is investigated at the state-averaged complete active space self-consistent field (SA-CASSCF) and extended multistate complete active space second-order perturbation theory (XMS-CASPT2) levels of theory. In addition, the asymmetrical MECI between the ground state (S0) and S1 of cyclopropanone is evaluated using SA-CASSCF, as well as (ME)CIs between the S1 and S2 states of benzene using SA-CASSCF and time-dependent density functional theory (TDDFT). Finally, a CI between the S1 and S2 excited states of thiophene was analyzed using TDDFT.
Collapse
Affiliation(s)
- Eva Vandaele
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Momir Mališ
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Sandra Luber
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| |
Collapse
|
15
|
Pradhan E, Zeng T. The Lack of Triplet Fusion for an Intramolecular Singlet Fission Chromophore: The Expected, the Unexpected, and a Reconciliation. J Phys Chem Lett 2024; 15:43-50. [PMID: 38127796 DOI: 10.1021/acs.jpclett.3c03238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Singlet fission (SF) has the potential to play a key role in photovoltaics since it generates a larger number of longer-lived triplet excitons after photoabsorption. Intramolecular SF (iSF) is of special interest since it enables tuning of SF efficiency by adjusting interchromophore configuration through covalent interaction. However, as elaborated in the present work, iSF chromophores are doomed to dissatisfy one general thermodynamic criterion for all SF chromophores, intramolecular or not: E(T2) ≥ 2E(T1), and therefore, the fusion of two triplet excitons to one triplet exciton is thermodynamically favorable. In our nonadiabatic quantum dynamics simulation for a model iSF chromophore, this expected fusion does not occur, because of the inefficient intersystem crossing hidden under the cover of internal conversion of the triplet fusion. A reconciliation is achieved between the dissatisfaction of E(T2) ≥ 2E(T1) and the large tetraradical character for general iSF chromophores.
Collapse
Affiliation(s)
- Ekadashi Pradhan
- Department of Chemistry, York University, Toronto, Ontario M3J1P3, Canada
| | - Tao Zeng
- Department of Chemistry, York University, Toronto, Ontario M3J1P3, Canada
| |
Collapse
|
16
|
Hetherington CV, Mohan T M N, Tilluck RW, Beck WF, Levine BG. Origin of Vibronic Coherences During Carrier Cooling in Colloidal Quantum Dots. J Phys Chem Lett 2023; 14:11651-11658. [PMID: 38109055 DOI: 10.1021/acs.jpclett.3c02384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Recent two-dimensional electronic spectroscopy experiments [Tilluck et al. J. Phys. Chem. Lett. 2021, 12 (39), 9677-9683] indicate the creation of coherent vibronic wavepackets in the first femtoseconds of hot carrier cooling in hexadecylamine-passivated CdSe quantum dots. Here we present a quantum chemical study of the origin of these coherences in a CdSe nanocrystal. We find that coherent wavepacket motions along vibrational coordinates with alkylamine character promote nonradiative relaxation through conical intersections between the exciton states of the inorganic core. Electronic excitations in the core are found to pass energy to the vibrations of the ligands via two distinct mechanisms: excitation of core phonon modes that are coupled to the ligand vibrations and direct excitation of ligand vibrations by delocalization of the exciton onto the ligands, both of which naturally arise within a photochemical framework based on many-electron potential energy surfaces. If these findings are demonstrated to be general, vibronic coherences may be leveraged to control photophysical outcomes in colloidal quantum dots.
Collapse
Affiliation(s)
- Caitlin V Hetherington
- Institute for Advanced Computational Science and Department of Chemistry, Stony Brook University Stony Brook, New York 11733 United States
| | - Nila Mohan T M
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 United States
| | - Ryan W Tilluck
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 United States
| | - Warren F Beck
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 United States
| | - Benjamin G Levine
- Institute for Advanced Computational Science and Department of Chemistry, Stony Brook University Stony Brook, New York 11733 United States
| |
Collapse
|
17
|
Taylor JT, Tozer DJ, Curchod BFE. On the description of conical intersections between excited electronic states with LR-TDDFT and ADC(2). J Chem Phys 2023; 159:214115. [PMID: 38059547 DOI: 10.1063/5.0176140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 11/14/2023] [Indexed: 12/08/2023] Open
Abstract
Conical intersections constitute the conceptual bedrock of our working understanding of ultrafast, nonadiabatic processes within photochemistry (and photophysics). Accurate calculation of potential energy surfaces within the vicinity of conical intersections, however, still poses a serious challenge to many popular electronic structure methods. Multiple works have reported on the deficiency of methods like linear-response time-dependent density functional theory within the adiabatic approximation (AA LR-TDDFT) or algebraic diagrammatic construction to second-order [ADC(2)]-approaches often used in excited-state molecular dynamics simulations-to describe conical intersections between the ground and excited electronic states. In the present study, we focus our attention on conical intersections between excited electronic states and probe the ability of AA LR-TDDFT and ADC(2) to describe their topology and topography, using protonated formaldimine and pyrazine as two exemplar molecules. We also take the opportunity to revisit the performance of these methods in describing conical intersections involving the ground electronic state in protonated formaldimine-highlighting in particular how the intersection ring exhibited by AA LR-TDDFT can be perceived either as a (near-to-linear) seam of intersection or two interpenetrating cones, depending on the magnitude of molecular distortions within the branching space.
Collapse
Affiliation(s)
- Jack T Taylor
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, United Kingdom
| | - David J Tozer
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, United Kingdom
| | - Basile F E Curchod
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| |
Collapse
|
18
|
Cuéllar-Zuquin J, Pepino AJ, Fdez. Galván I, Rivalta I, Aquilante F, Garavelli M, Lindh R, Segarra-Martí J. Characterizing Conical Intersections in DNA/RNA Nucleobases with Multiconfigurational Wave Functions of Varying Active Space Size. J Chem Theory Comput 2023; 19:8258-8272. [PMID: 37882796 PMCID: PMC10851440 DOI: 10.1021/acs.jctc.3c00577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 10/13/2023] [Accepted: 10/13/2023] [Indexed: 10/27/2023]
Abstract
We characterize the photochemically relevant conical intersections between the lowest-lying accessible electronic excited states of the different DNA/RNA nucleobases using Cholesky decomposition-based complete active space self-consistent field (CASSCF) algorithms. We benchmark two different basis set contractions and several active spaces for each nucleobase and conical intersection type, measuring for the first time how active space size affects conical intersection topographies in these systems and the potential implications these may have toward their description of photoinduced phenomena. Our results show that conical intersection topographies are highly sensitive to the electron correlation included in the model: by changing the amount (and type) of correlated orbitals, conical intersection topographies vastly change, and the changes observed do not follow any converging pattern toward the topographies obtained with the largest and most correlated active spaces. Comparison across systems shows analogous topographies for almost all intersections mediating population transfer to the dark 1nO/Nπ* states, while no similarities are observed for the "ethylene-like" conical intersection ascribed to mediate the ultrafast decay component to the ground state in all DNA/RNA nucleobases. Basis set size seems to have a minor effect, appearing to be relevant only for purine-based derivatives. We rule out structural changes as a key factor in classifying the different conical intersections, which display almost identical geometries across active space and basis set change, and we highlight instead the importance of correctly describing the electronic states involved at these crossing points. Our work shows that careful active space selection is essential to accurately describe conical intersection topographies and therefore to adequately account for their active role in molecular photochemistry.
Collapse
Affiliation(s)
- Juliana Cuéllar-Zuquin
- Instituto
de Ciencia Molecular, Universitat de Valencia, P.O. Box 22085, ES-46071 Valencia, Spain
| | - Ana Julieta Pepino
- Dipartimento
di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale del Risorgimento 4, I-40136 Bologna, Italy
| | - Ignacio Fdez. Galván
- Department
of Chemistry − BMC, Uppsala University, P.O. Box 576, SE-75123 Uppsala, Sweden
| | - Ivan Rivalta
- Dipartimento
di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale del Risorgimento 4, I-40136 Bologna, Italy
- ENSL,
CNRS, Laboratoire de Chimie UMR 5182, 46 Allée d’Italie, 69364 Lyon, France
| | - Francesco Aquilante
- Theory
and Simulation of Materials (THEOS), and National Centre for Computational
Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Marco Garavelli
- Dipartimento
di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale del Risorgimento 4, I-40136 Bologna, Italy
| | - Roland Lindh
- Department
of Chemistry − BMC, Uppsala University, P.O. Box 576, SE-75123 Uppsala, Sweden
| | - Javier Segarra-Martí
- Instituto
de Ciencia Molecular, Universitat de Valencia, P.O. Box 22085, ES-46071 Valencia, Spain
| |
Collapse
|
19
|
Mansour R, Toldo JM, Mukherjee S, Pinheiro M, Barbatti M. Temperature effects on the internal conversion of excited adenine and adenosine. Phys Chem Chem Phys 2023; 25:27083-27093. [PMID: 37801041 PMCID: PMC10583498 DOI: 10.1039/d3cp03234e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 09/09/2023] [Indexed: 10/07/2023]
Abstract
This work aims to elucidate the dependence of the excited-state lifetime of adenine and adenosine on temperature. So far, it has been experimentally shown that while adenine's lifetime is unaffected by temperature, adenosine's lifetime strongly depends on it. However, the non-Arrhenius temperature dependence has posed a challenge in explaining this phenomenon. We used surface hopping to simulate the dynamics of adenine and adenosine in the gas phase at 0 and 400 K. The temperature effects were observed under the initial conditions via Wigner sampling with thermal corrections. Our results confirm that adenine's excited-state lifetime does not depend on temperature, while adenosine's lifetime does. Adenosine's dependency is due to intramolecular vibrational energy transfer from adenine to the ribose group. At 0 K, this transfer reduced the mean kinetic energy of adenine's moiety so much that internal conversion is inhibited, and the lifetime elongated by a factor of 2.3 compared to that at 400 K. The modeling also definitively ruled out the influence of viscosity, which was proposed as an alternative explanation previously.
Collapse
Affiliation(s)
- Ritam Mansour
- Aix Marseille University, CNRS, ICR, Marseille, France.
| | | | | | - Max Pinheiro
- Aix Marseille University, CNRS, ICR, Marseille, France.
| | - Mario Barbatti
- Aix Marseille University, CNRS, ICR, Marseille, France.
- Institut Universitaire de France, 75231, Paris, France
| |
Collapse
|
20
|
Vörös D, Mai S. Role of Ultrafast Internal Conversion and Intersystem Crossing in the Nonadiabatic Relaxation Dynamics of ortho-Nitrobenzaldehyde. J Phys Chem A 2023. [PMID: 37405967 PMCID: PMC10364085 DOI: 10.1021/acs.jpca.3c02899] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/07/2023]
Abstract
ortho-Nitrobenzaldehyde (oNBA) is a well-known photoactivated acid and a prototypical photolabile nitro-aromatic compound. Despite extensive investigations, the ultrafast relaxation dynamics of oNBA is still not properly understood, especially concerning the role of the triplet states. In this work, we provide an in-depth picture of this dynamics by combining single- and multireference electronic structure methods with potential energy surface exploration and nonadiabatic dynamics simulations using the Surface Hopping including ARbitary Couplings (SHARC) approach. Our results reveal that the initial decay from the bright ππ* state to the S1 minimum is barrierless. It involves three changes in electronic structure from ππ* (ring) to nπ* (nitro group), to nπ* (aldehyde group), and then to another nπ* (nitro group). The decay of the ππ* takes 60-80 fs and can be tracked with time-resolved luminescence spectroscopy, where we predict for the first time a short-lived coherence of the luminescence energy with a 25 fs period. Intersystem crossing can occur already during the S4 → S1 deactivation cascade but also from S1, with a time constant of about 2.4 ps and such that first a triplet ππ* state localized on the nitro group is populated. The triplet population first evolves into an nπ* and then quickly undergoes hydrogen transfer to form a biradical intermediate, from where the ketene is eventually produced. The majority of the excited population decays from S1 through two conical intersections of equal utilization, a previously unreported one involving a scissoring motion of the nitro group that leads back to the oNBA ground state and the one involving hydrogen transfer that leads to the ketene intermediate.
Collapse
Affiliation(s)
- Dóra Vörös
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria
- Vienna Doctoral School in Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Sebastian Mai
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria
| |
Collapse
|
21
|
Fdez Galván I, Lindh R. Smooth Things Come in Threes: A Diabatic Surrogate Model for Conical Intersection Optimization. J Chem Theory Comput 2023. [PMID: 37192531 DOI: 10.1021/acs.jctc.3c00389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The optimization of conical intersection structures is complicated by the nondifferentiability of the adiabatic potential energy surfaces. In this work, we build a pseudodiabatic surrogate model, based on Gaussian process regression, formed by three smooth and differentiable surfaces that can adequately reproduce the adiabatic surfaces. Using this model with the restricted variance optimization method results in a notable decrease of the overall computational effort required to obtain minimum energy crossing points.
Collapse
Affiliation(s)
- Ignacio Fdez Galván
- Department of Chemistry-BMC, Uppsala University, P.O. Box 576, SE-75123 Uppsala, Sweden
| | - Roland Lindh
- Department of Chemistry-BMC, Uppsala University, P.O. Box 576, SE-75123 Uppsala, Sweden
- Uppsala Center for Computational Chemistry (UC3), Uppsala University, P.O. Box 576, SE-75123 Uppsala, Sweden
| |
Collapse
|
22
|
Pracht P, Bannwarth C. Finding Excited-State Minimum Energy Crossing Points on a Budget: Non-Self-Consistent Tight-Binding Methods. J Phys Chem Lett 2023; 14:4440-4448. [PMID: 37144783 DOI: 10.1021/acs.jpclett.3c00494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The automated exploration and identification of minimum energy conical intersections (MECIs) is a valuable computational strategy for the study of photochemical processes. Due to the immense computational effort involved in calculating non-adiabatic derivative coupling vectors, simplifications have been introduced focusing instead on minimum energy crossing points (MECPs), where promising attempts were made with semiempirical quantum mechanical methods. A simplified treatment for describing crossing points between almost arbitrary diabatic states based on a non-self-consistent extended tight-binding method, GFN0-xTB, is presented. Involving only a single diagonalization of the Hamiltonian, the method can provide energies and gradients for multiple electronic states, which can be used in a derivative coupling-vector-free scheme to calculate MECPs. By comparison with high-lying MECIs of benchmark systems, it is demonstrated that the identified geometries are good starting points for further MECI refinement with ab initio methods.
Collapse
Affiliation(s)
- Philipp Pracht
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Christoph Bannwarth
- Institute for Physical Chemistry, RWTH Aachen University, Melatener Str. 20, 52074 Aachen, Germany
| |
Collapse
|
23
|
Pradhan E, Zeng T. Triplet Separation after the Fastest Intramolecular Singlet Fission in the Smallest Chromophore. J Chem Theory Comput 2023; 19:2092-2101. [PMID: 36966419 DOI: 10.1021/acs.jctc.3c00096] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/27/2023]
Abstract
Singlet fission is of key importance in harvesting solar energy in solar cells, as it generates a pair of triplet excitons on the incidence of a photon. This phenomenon is not yet widely employed in the organic photovoltaics industry mostly because of the rarity of singlet fission chromophores. Pyrazino[2,3-g]quinoxaline-1,4,6,9-tetraoxide was recently designed as the smallest intramolecular singlet fission chromophore, and it undergoes the fastest singlet fission with a 16 fs time scale. The subsequent separation of the generated triplet-pair is of likewise importance as their efficient generation. Through quantum chemistry calculations and quantum dynamics simulations, we show that the triplet-pair separates to residing on two chromophores with an ∼80% probability on each collision between a chromophore with the triplet-pair and a ground state chromophore. Avoided crossing, instead of conical intersection, is involved in the efficient exciton separation.
Collapse
Affiliation(s)
- Ekadashi Pradhan
- Department of Chemistry, York University, Toronto, Ontario M3J1P3, Canada
| | - Tao Zeng
- Department of Chemistry, York University, Toronto, Ontario M3J1P3, Canada
| |
Collapse
|
24
|
Zhao X, Shu Y, Zhang L, Xu X, Truhlar DG. Direct Nonadiabatic Dynamics of Ammonia with Curvature-Driven Coherent Switching with Decay of Mixing and with Fewest Switches with Time Uncertainty: An Illustration of Population Leaking in Trajectory Surface Hopping Due to Frustrated Hops. J Chem Theory Comput 2023; 19:1672-1685. [PMID: 36877830 DOI: 10.1021/acs.jctc.2c01260] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
Abstract
Mixed quantum-classical nonadiabatic dynamics is a widely used approach to simulate molecular dynamics involving multiple electronic states. There are two main categories of mixed quantum-classical nonadiabatic dynamics algorithms, namely, trajectory surface hopping (TSH) in which the trajectory propagates on a single potential energy surface, interrupted by hops, and self-consistent-potential (SCP) methods, such as semiclassical Ehrenfest, in which propagation occurs on a mean-field surface without hops. In this work, we will illustrate an example of severe population leaking in TSH. We emphasize that such leaking is a combined effect of frustrated hops and long-time simulations that drive the final excited-state population toward zero as a function of time. We further show that such leaking can be alleviated-but not eliminated-by the fewest switches with time uncertainty TSH algorithm (here implemented in the SHARC program); the time uncertainty algorithm slows down the leaking process by a factor of 4.1. The population leaking is not present in coherent switching with decay of mixing (CSDM), which is an SCP method with non-Markovian decoherence included. Another result in this paper is that we find very similar results with the original CSDM algorithm, with time-derivative CSDM (tCSDM), and with curvature-driven CSDM (κCSDM). Not only do we find good agreement for electronically nonadiabatic transition probabilities but also we find good agreement of the norms of the effective nonadiabatic couplings (NACs) that are derived from the curvature-driven time-derivative couplings as implemented in κCSDM with the time-dependent norms of the nonadiabatic coupling vectors computed by state-averaged complete-active-space self-consistent field theory.
Collapse
Affiliation(s)
- Xiaorui Zhao
- Center for Combustion Energy, Tsinghua University, Beijing 100084, P. R. China.,School of Aerospace Engineering, Tsinghua University, Beijing 100084, P. R. China
| | - Yinan Shu
- Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Linyao Zhang
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Xuefei Xu
- Center for Combustion Energy, Tsinghua University, Beijing 100084, P. R. China
| | - Donald G Truhlar
- Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| |
Collapse
|
25
|
Huang X, Pei Z, Liang W. Analytical derivative couplings within the framework of time-dependent density functional theory coupled with conductor-like polarizable continuum model: Formalism, implementation, and applications. J Chem Phys 2023; 158:044122. [PMID: 36725492 DOI: 10.1063/5.0130617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The nonadiabatic phenomena, which are characterized by a strong coupling between electronic and nuclear motions, are ubiquitous. The nonadiabatic effect of the studied system can be significantly affected by the surrounding environment, such as solvents, in which such nonadiabatic process takes place. It is essential to develop the theoretical models to simulate these processes while accurately modeling the solvent environment. The time-dependent density functional theory (TDDFT) is currently the most efficient approach to describe the electronic structures and dynamics of complex systems, while the polarizable continuum model (PCM) represents one of the most successful examples among continuum solvation models. Here, we formulate the first-order derivative couplings (DCs) between the ground and excited states as well as between two excited states by utilizing time-independent equation of motion formalism within the framework of both linear response and spin flip formulations of TDDFT/CPCM (the conductor-like PCM), and implement the analytical DCs into the Q-CHEM electronic structure software package. The analytic implementation is validated by the comparison of the analytical and finite-difference results, and reproducing geometric phase effect in the protonated formaldimine test case. Taking 4-(N,N-dimethylamino)benzonitrile and uracil in the gas phase and solution as an example, we demonstrate that the solvent effect is essential not only for the excitation energies of the low-lying excited-states but also for the DCs between these states. Finally, we calculate the internal conversion rate of benzophenone in a solvent with DC being used. The current implementation of analytical DCs together with the existing analytical gradient and Hessian of TDDFT/PCM excited states allows one to study the nonadiabatic effects of relatively large systems in solutions with low computational cost.
Collapse
Affiliation(s)
- Xunkun Huang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
| | - Zheng Pei
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
| | - WanZhen Liang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
| |
Collapse
|
26
|
Chen WK, Fang WH, Cui G. Extending multi-layer energy-based fragment method for excited-state calculations of large covalently bonded fragment systems. J Chem Phys 2023; 158:044110. [PMID: 36725521 DOI: 10.1063/5.0129458] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Recently, we developed a low-scaling Multi-Layer Energy-Based Fragment (MLEBF) method for accurate excited-state calculations and nonadiabatic dynamics simulations of nonbonded fragment systems. In this work, we extend the MLEBF method to treat covalently bonded fragment ones. The main idea is cutting a target system into many fragments according to chemical properties. Fragments with dangling bonds are first saturated by chemical groups; then, saturated fragments, together with the original fragments without dangling bonds, are grouped into different layers. The accurate total energy expression is formulated with the many-body energy expansion theory, in combination with the inclusion-exclusion principle that is used to delete the contribution of chemical groups introduced to saturate dangling bonds. Specifically, in a two-layer MLEBF model, the photochemically active and inert layers are calculated with high-level and efficient electronic structure methods, respectively. Intralayer and interlayer energies can be truncated at the two- or three-body interaction level. Subsequently, through several systems, including neutral and charged covalently bonded fragment systems, we demonstrate that MLEBF can provide accurate ground- and excited-state energies and gradients. Finally, we realize the structure, conical intersection, and path optimizations by combining our MLEBF program with commercial and free packages, e.g., ASE and SciPy. These developments make MLEBF a practical and reliable tool for studying complex photochemical and photophysical processes of large nonbonded and bonded fragment systems.
Collapse
Affiliation(s)
- Wen-Kai Chen
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Wei-Hai Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| |
Collapse
|
27
|
Understanding the photodynamics of 3-hydroxypyran-4-one using surface hopping simulations. J Photochem Photobiol A Chem 2023. [DOI: 10.1016/j.jphotochem.2023.114538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
28
|
Rao AG, Schapiro I. Photoisomerization of phytochrome chromophore models: an XMS-CASPT2 study. Phys Chem Chem Phys 2022; 24:29393-29405. [PMID: 36468544 DOI: 10.1039/d2cp04249e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Phytochromes are a superfamily of photoreceptors that harbor linear tetrapyrroles as chromophores. Upon light illumination, the linear tetrapyrrole chromophore undergoes a double bond isomerization which starts a photocycle. In this work, we studied the photoisomerization of chromophore models designed based on the C- and D-rings of the phycocyanobilin (PCB) chromophore. In total, five different models with varying substitutions were investigated. Firstly, the vertical excitation energies were benchmarked using different computational methods to establish the relative order of the excited states. Based on these calculations, we computed the photoisomerization profiles using the extended multi-state (XMS) version of the CASPT2 method. The profiles were obtained for both the clockwise and counterclockwise rotations of the C15C16 bond in the Z and E isomers using a linear interpolation of internal coordinates between the Franck-Condon and MECI geometries. In the minimal chromophore model that lacks the substitutions at the pyrrole rings, the isomerization involves both C14-C15 and C15C16 bonds of the methine bridge between the C- and D-rings, resembling the hula-twist motion. The MECIs are characterized by a partial charge transfer between the two pyrrole rings pointing towards a twisted intramolecular charge transfer. Systematic introduction of substituents leads to an increase in the steric repulsion between the two pyrrole rings causing a pretwist of the dihedral around the C15C16 bond, which creates a preference for the counterclockwise isomerization. An introduction of the carbonyl group at the D-ring increases the extent of charge transfer which changes the isomerization mechanism from hula-twist to one-bond flip.
Collapse
Affiliation(s)
- Aditya G Rao
- Fritz Haber Center for Molecular Dynamics Research, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
| | - Igor Schapiro
- Fritz Haber Center for Molecular Dynamics Research, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
| |
Collapse
|
29
|
Zhang L, Shu Y, Bhaumik S, Chen X, Sun S, Huang Y, Truhlar DG. Nonadiabatic Dynamics of 1,3-Cyclohexadiene by Curvature-Driven Coherent Switching with Decay of Mixing. J Chem Theory Comput 2022; 18:7073-7081. [PMID: 36350795 DOI: 10.1021/acs.jctc.2c00801] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The photoinduced ring-opening reaction of 1,3-cyclohexadiene to produce 1,3,5-hexatriene is a classic electrocyclic reaction and is also a prototype for many reactions of biological and synthetic importance. Here, we simulate the ultrafast nonadiabatic dynamics of the reaction in the manifold of the three lowest valence electronic states by using extended multistate complete-active-space second-order perturbation theory (XMS-CASPT2) combined with the curvature-driven coherent switching with decay of mixing (κCSDM) dynamical method. We obtain an excited-state lifetime of 79 fs, and a product quantum yield of 40% from the 500 trajectories initiated in the S1 excited state. The obtained lifetime and quantum yield values are very close to previously reported experimental and computed values, showing the capability of performing a reasonable nonadiabatic ring-opening dynamics with the κCSDM method that does not require nonadiabatic coupling vectors, time derivatives, or diabatization. In addition, we study the ring-opening reaction by initiating the trajectories in the dark state S2. We also optimize the S0/S1 and S1/S2 minimum-energy conical intersections (MECIs) by XMS-CASPT2; for S1/S2, we optimized both an inner and an outer local-minimum-energy conical intersections (LMECIs). We provide the potential energy profile along the ring-opening coordinate by joining selected critical points via linear synchronous transit paths. We find the inner S1/S2 LMECI to be more crucial than the outer one.
Collapse
Affiliation(s)
- Linyao Zhang
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China.,School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Yinan Shu
- Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Suman Bhaumik
- Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Xiye Chen
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China.,School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Shaozeng Sun
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Yudong Huang
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Donald G Truhlar
- Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| |
Collapse
|
30
|
Filiba O, Borin VA, Schapiro I. The involvement of triplet states in the isomerization of retinaloids. Phys Chem Chem Phys 2022; 24:26223-26231. [PMID: 36278932 DOI: 10.1039/d2cp03791b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Rhodopsins form a family of photoreceptor proteins which utilize the retinal chromophore for light energy conversion. Upon light absorption the retinal chromophore undergoes a photoisomerization. This reaction involves a non-radiative relaxation through a conical intersection between the singlet excited state and the ground state. In this work we studied the possible involvement of triplet states in the photoisomerization of retinaloids using the extended multistate (XMS) version of CASPT2. To this end, truncated models of three retinaloids were considered: protonated Schiff base, deprotonated Schiff base and the aldehyde form. The optimized geometries of the reactant, the product and the conical intersection were connected by a linear interpolation of internal coordinates to describe the isomerization. The energetic position of the low-lying singlet and triplet states as well as their spin-orbit coupling matrix elements (SOCME) were calculated along the isomerization profile. The SOCME values peaked in vicinity of the conical intersection for all the retinaloids. Furthermore, the magnitude of SOCME is invariant to the number of double bonds in the model. The SOCME for the protonated Schiff base is negligible (1.5 cm-1) which renders the involvement of the triplet state as improbable. However, the largest SOCME value of 30 cm-1 was found for the aldehyde form, followed by 15 cm-1 for the deprotonated Schiff base.
Collapse
Affiliation(s)
- Ofer Filiba
- Fritz Haber Research Center for Molecular Dynamics and Institute of Chemistry, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel.
| | - Veniamin A Borin
- Fritz Haber Research Center for Molecular Dynamics and Institute of Chemistry, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel.
| | - Igor Schapiro
- Fritz Haber Research Center for Molecular Dynamics and Institute of Chemistry, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel.
| |
Collapse
|
31
|
Towards the engineering of a photon-only two-stroke rotary molecular motor. Nat Commun 2022; 13:6433. [PMID: 36307476 PMCID: PMC9616945 DOI: 10.1038/s41467-022-33695-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 09/27/2022] [Indexed: 12/25/2022] Open
Abstract
The rational engineering of photoresponsive materials, e.g., light-driven molecular motors, is a challenging task. Here, we use structure-related design rules to prepare a prototype molecular rotary motor capable of completing an entire revolution using, exclusively, the sequential absorption of two photons; i.e., a photon-only two-stroke motor. The mechanism of rotation is then characterised using a combination of non-adiabatic dynamics simulations and transient absorption spectroscopy measurements. The results show that the rotor moiety rotates axially relative to the stator and produces, within a few picoseconds at ambient T, an intermediate with the same helicity as the starting structure. We discuss how such properties, that include a 0.25 quantum efficiency, can help overcome the operational limitations of the classical overcrowded alkene designs.
Collapse
|
32
|
Synergistic interplay between photoisomerization and photoluminescence in a light-driven rotary molecular motor. Nat Commun 2022; 13:5765. [PMID: 36180434 PMCID: PMC9525625 DOI: 10.1038/s41467-022-33177-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/06/2022] [Indexed: 12/03/2022] Open
Abstract
Photoactuators and photoluminescent dyes utilize light to perform mechanical motion and undergo spontaneous radiation emission, respectively. Combining these two functionalities in a single molecule would benefit the construction of advanced molecular machines. Due to the possible detrimental interaction between the two light-dependent functional parts, the design of hybrid systems featuring both functions in parallel remains highly challenging. Here, we develop a light-driven rotary molecular motor with an efficient photoluminescent dye chemically attached to the motor, not compromising its motor function. This molecular system shows efficient rotary motion and bright photoluminescence, and these functions can be addressed by a proper choice of excitation wavelengths and solvents. The moderate interaction between the two parts generates synergistic effects, which are beneficial for lower-energy excitation and chirality transfer from the motor to the photoluminescent dye. Our results provide prospects towards photoactive multifunctional systems capable of carrying out molecular rotary motion and tracking its location in a complex environment. Combining photofunctionalities in a single molecule is challenging due to inherent detrimental interactions. Here, the authors construct a molecular motor that exhibits photoinduced rotary motion together with bright photoluminescence.
Collapse
|
33
|
Pracht P, Bannwarth C. Fast Screening of Minimum Energy Crossing Points with Semiempirical Tight-Binding Methods. J Chem Theory Comput 2022; 18:6370-6385. [PMID: 36121838 DOI: 10.1021/acs.jctc.2c00578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The investigation of photochemical processes is a highly active field in computational chemistry. One research direction is the automated exploration and identification of minimum energy conical intersection (MECI) geometries. However, due to the immense technical effort required to calculate nonadiabatic potential energy landscapes, the routine application of such computational protocols is severely limited. In this study, we will discuss the prospect of combining adiabatic potential energy surfaces from semiempirical quantum mechanical calculations with specialized confinement potential and metadynamics simulations to identify S0/T1 minimum energy crossing point (MECP) geometries. It is shown that MECPs calculated at the GFN2-xTB level can provide suitable approximations to high-level S0/S1ab initio conical intersection geometries at a fraction of the computational cost. Reference MECIs of benzene are studied to illustrate the basic concept. An example application of the presented protocol is demonstrated for a set of photoswitch molecules.
Collapse
Affiliation(s)
- Philipp Pracht
- Institute of Physical Chemistry, RWTH Aachen University, Melatener Str. 20, 52056Aachen, Germany
| | - Christoph Bannwarth
- Institute of Physical Chemistry, RWTH Aachen University, Melatener Str. 20, 52056Aachen, Germany
| |
Collapse
|
34
|
Hutton L, Curchod BFE. Photodynamics of Gas‐Phase Pyruvic Acid Following Light Absorption in the Actinic Region. CHEMPHOTOCHEM 2022. [DOI: 10.1002/cptc.202200151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Lewis Hutton
- Centre for Computational Chemistry School of Chemistry University of Bristol Bristol BS8 1TS UK
| | - Basile F. E. Curchod
- Centre for Computational Chemistry School of Chemistry University of Bristol Bristol BS8 1TS UK
| |
Collapse
|
35
|
Mandal S, Srinivasan V. Rationalizing the Unexpected Sensitivity in Excited State Lifetimes of Adenine to Tautomerization by Nonadiabatic Molecular Dynamics. J Phys Chem B 2022; 126:7077-7087. [PMID: 36083211 DOI: 10.1021/acs.jpcb.2c03178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The remarkable photostability of canonical nucleobases makes them ideal building blocks for DNA and RNA. Even minor structural changes are expected to lead to drastic alteration of their subpicosecond excited state lifetimes. However, it is interesting to note that while the 9H- and 7H-amino tautomers of adenine possess drastically different lifetimes, 9H- and 7H-keto guanine possess similar excited state lifetimes. With an aim to explain this unexpected difference in sensitivity of lifetimes to tautomerization, we have investigated the excited state relaxation mechanism of UV-excited adenine and guanine tautomers using surface hopping based nonadiabatic molecular dynamics. We find that internal conversion in both guanine tautomers is almost barrierless while both adenine tautomers encounter significant barriers before they can deactivate. Moreover, the major deactivation channel (C2-puckering) in 9H-amino adenine is overall more efficient than the one (C6-puckering) in the 7H-amino form. We trace this difference to the frequent rotation of the amino group which disrupts its conjugation with the heterocyclic ring thereby reducing the strength of nonadiabatic coupling and, hence, delaying internal conversion.
Collapse
Affiliation(s)
- Satyajit Mandal
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal 462 066, India
| | - Varadharajan Srinivasan
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal 462 066, India
| |
Collapse
|
36
|
Nag P, Bera A, Vennapusa SR. Rapid Intersystem Crossing Induced by Ultrafast Excited-State Intramolecular Proton Transfer in 3-Mercaptopyran-4-one. J Phys Chem A 2022; 126:6407-6415. [PMID: 36069738 DOI: 10.1021/acs.jpca.2c04205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Investigation into the photoinduced processes of 3-mercaptopyran-4-one is carried out using trajectory-based surface hopping simulations. Excitation into the near-degenerate higher singlet excited states reveals rapid internal conversion (IC) into S1 on a sub-50 fs timescale. Excited-state intramolecular proton transfer (ESIPT) also takes place simultaneously with IC. We observe that following tautomerization, the molecule has multiple relaxation pathways. A channel exists for it to nonradiatively decay into the tautomer ground-state or undergo rapid intersystem crossing (ISC) into the close-lying higher triplet state, which ultimately decays into T1. The simulations show that ISC is significantly enhanced after ESIPT, which is studied by tracking the changes in energy gaps and associated spin-orbit coupling elements.
Collapse
Affiliation(s)
- Probal Nag
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura, Thiruvananthapuram, Kerala 695551, India
| | - Anshuman Bera
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura, Thiruvananthapuram, Kerala 695551, India
| | - Sivaranjana Reddy Vennapusa
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura, Thiruvananthapuram, Kerala 695551, India
| |
Collapse
|
37
|
Bertram L, Roberts SJ, Powner MW, Szabla R. Photochemistry of 2-thiooxazole: a plausible prebiotic precursor to RNA nucleotides. Phys Chem Chem Phys 2022; 24:21406-21416. [PMID: 36047336 PMCID: PMC7613695 DOI: 10.1039/d2cp03167a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Potentially prebiotic chemical reactions leading to RNA nucleotides involve periods of UV irradiation, which are necessary to promote selectivity and destroy biologially irrelevant side products. Nevertheless, UV light has only been applied to promote specific stages of prebiotic reactions and its effect on complete prebiotic reaction sequences has not been extensively studied. Here, we report on an experimental and computational investigation of the photostability of 2-thiooxazole (2-TO), a potential precursor of pyrimidine and 8-oxopurine nucleotides on early Earth. Our UV-irradiation experiments resulted in rapid decomposition of 2-TO into unidentified small molecule photoproducts. We further clarify the underlying photochemistry by means of accurate ab initio calculations and surface hopping molecular dynamics simulations. Overall, the computational results show efficient rupture of the aromatic ring upon the photoexcitation of 2-TO via breaking of the C-O bond. Consequently, the initial stage of the divergent prebiotic synthesis of pyrimidine and 8-oxopurine nucleotides would require periodic shielding from UV light either with sun screening chromophores or through a planetary scenario that would protect 2-TO until it is transformed into a more stable intermediate compound, e.g. oxazolidinone thione.
Collapse
Affiliation(s)
- Lauren Bertram
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK
| | - Samuel J Roberts
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.,MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Matthew W Powner
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
| | - Rafał Szabla
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK.,Department of Physical and Quantum Chemistry, Faculty of Chemistry, Wrocław University of Science and Technology, 50-370 Wrocław, Poland.
| |
Collapse
|
38
|
Valverde D, Mai S, Canuto S, Borin AC, González L. Ultrafast Intersystem Crossing Dynamics of 6-Selenoguanine in Water. JACS AU 2022; 2:1699-1711. [PMID: 35911449 PMCID: PMC9327080 DOI: 10.1021/jacsau.2c00250] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Rationalizing the photochemistry of nucleobases where an oxygen is replaced by a heavier atom is essential for applications that exploit near-unity triplet quantum yields. Herein, we report on the ultrafast excited-state deactivation mechanism of 6-selenoguanine (6SeGua) in water by combining nonadiabatic trajectory surface-hopping dynamics with an electrostatic embedding quantum mechanics/molecular mechanics (QM/MM) scheme. We find that the predominant relaxation mechanism after irradiation starts on the bright singlet S2 state that converts internally to the dark S1 state, from which the population is transferred to the triplet T2 state via intersystem crossing and finally to the lowest T1 state. This S2 → S1 → T2 → T1 deactivation pathway is similar to that observed for the lighter 6-thioguanine (6tGua) analogue, but counterintuitively, the T1 lifetime of the heavier 6SeGua is shorter than that of 6tGua. This fact is explained by the smaller activation barrier to reach the T1/S0 crossing point and the larger spin-orbit couplings of 6SeGua compared to 6tGua. From the dynamical simulations, we also calculate transient absorption spectra (TAS), which provide two time constants (τ1 = 131 fs and τ2 = 191 fs) that are in excellent agreement with the experimentally reported value (τexp = 130 ± 50 fs) (Farrel et al. J. Am. Chem. Soc. 2018, 140, 11214). Intersystem crossing itself is calculated to occur with a time scale of 452 ± 38 fs, highlighting that the TAS is the result of a complex average of signals coming from different nonradiative processes and not intersystem crossing alone.
Collapse
Affiliation(s)
- Danillo Valverde
- Department
of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Avenida Professor Lineu Prestes, 748, São Paulo, São Paulo CEP 05508-000, Brazil
- Institute
of Physics, University of São Paulo, Rua do Matão 1371, São Paulo, São Paulo CEP 05508-090, Brazil
| | - Sebastian Mai
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, Vienna 1090, Austria
| | - Sylvio Canuto
- Institute
of Physics, University of São Paulo, Rua do Matão 1371, São Paulo, São Paulo CEP 05508-090, Brazil
| | - Antonio Carlos Borin
- Department
of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Avenida Professor Lineu Prestes, 748, São Paulo, São Paulo CEP 05508-000, Brazil
| | - Leticia González
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, Vienna 1090, Austria
| |
Collapse
|
39
|
Wong NGK, Rankine CD, Anstöter CS, Dessent CEH. Photostability of the deprotonated forms of the UV filters homosalate and octyl salicylate: molecular dissociation versus electron detachment following UV excitation. Phys Chem Chem Phys 2022; 24:17068-17076. [PMID: 35791920 PMCID: PMC9301628 DOI: 10.1039/d2cp01612e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
While common molecular anions show a strong propensity to undergo electron detachment upon UV excitation, this process often occurs in competition with molecular ion dissociation. The factors that affect the balance between these two major possible decay pathways have not been well understood to date. Laser photodissociation spectroscopy of the deprotonated forms of the UV filter molecules, Homosalate (HS) and Octyl Salicylate (OS), i.e. [HS - H]- and [OS - H]-, was used to acquire gas-phase UV absorption spectra for [HS - H]- and [OS - H]-via photodepletion from 3.0-5.8 eV. No photofragmentation (i.e. dissociation of the ionic molecular framework) was observed for either [HS - H]- and [OS - H]- following photoexcitation, revealing that electron loss entirely dominates the electronic decay pathways for these systems. High-level quantum chemical calculations were used to map out the excited states associated with [HS - H]- and [OS - H]-, revealing that the minimum-energy crossing points (MECPs) between the S1 and S0 states are located in elevated regions of the potential energy surface, making internal conversion unlikely. These results are consistent with our experimental observation that electron detachment out-competes hot ground state molecular fragmentation. More generally, our results reveal that the competition between molecular dissociation and electron detachment following anion photoexcitation can be determined by the magnitude of the energy gap between the excitation energy and the MECPs, rather than being a simple function of whether the excitation energy lies above the anion's vertical detachment energy.
Collapse
Affiliation(s)
- Natalie G K Wong
- Department of Chemistry, University of York, Heslington, YO10 5DD, UK.
| | - Conor D Rankine
- Chemistry - School of Natural and Environmental Sciences, Newcastle University, Newcastle, upon Tyne, UK
| | - Cate S Anstöter
- Department of Chemistry, University of York, Heslington, YO10 5DD, UK.
| | | |
Collapse
|
40
|
Mansour R, Toldo JM, Barbatti M. Role of the Hydrogen Bond on the Internal Conversion of Photoexcited Adenosine. J Phys Chem Lett 2022; 13:6194-6199. [PMID: 35767744 DOI: 10.1021/acs.jpclett.2c01554] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Experiments and theory have revealed that hydrogen bonds modify the excited-state lifetimes of nucleosides compared to nucleobases. Nevertheless, how these bonds impact the internal conversion is still unsettled. This work simulates the non-adiabatic dynamics of adenosine conformers in the gas phase with and without hydrogen bonds between the sugar and adenine moieties. The isomer containing the hydrogen bond (syn) exhibits a significantly shorter excited-state lifetime than the isomer without it (anti). However, internal conversion through electron-driven proton transfer between sugar and adenine plays only a minor (although non-negligible) role in the photophysics of adenosine. Either with or without hydrogen bonds, photodeactivation preferentially occurs following the ring-puckering pathways. The role of the hydrogen bond is to avoid the sugar rotation relative to adenine, shortening the distance to the ring-puckering internal conversion.
Collapse
Affiliation(s)
- Ritam Mansour
- Aix Marseille University, CNRS, ICR, Marseille 13397, France
| | - Josene M Toldo
- Aix Marseille University, CNRS, ICR, Marseille 13397, France
| | - Mario Barbatti
- Aix Marseille University, CNRS, ICR, Marseille 13397, France
- Institut Universitaire de France, 75231 Paris, France
| |
Collapse
|
41
|
Nishimoto Y, Battaglia S, Lindh R. Analytic First-Order Derivatives of (X)MS, XDW, and RMS Variants of the CASPT2 and RASPT2 Methods. J Chem Theory Comput 2022; 18:4269-4281. [PMID: 35699280 DOI: 10.1021/acs.jctc.2c00301] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Crossings between states involve complex electronic structures, making the accurate characterization of the crossing point difficult. In this study, the analytic derivatives of three complete active space second-order perturbation theory (CASPT2) variants as well as an extension of the restricted active space (RASPT2) are developed. These variants are applied to locating minimum energy conical intersections. Our results demonstrate that the three CASPT2 variants predict qualitatively similar results, but a recently developed variant, the rotated multistate CASPT2 (RMS-CASPT2), is least sensitive to the number of states considered in the calculation. We demonstrate that CASPT2 and the reference self-consistent field calculations predict qualitatively different energetics and bond lengths.
Collapse
Affiliation(s)
- Yoshio Nishimoto
- Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Stefano Battaglia
- Department of Chemistry - BMC, Uppsala University, P.O. Box 576, SE-75123 Uppsala, Sweden
| | - Roland Lindh
- Department of Chemistry - BMC, Uppsala University, P.O. Box 576, SE-75123 Uppsala, Sweden
| |
Collapse
|
42
|
Mansour R, Mukherjee S, Pinheiro M, Noble JA, Jouvet C, Barbatti M. Pre-Dewar structure modulates protonated azaindole photodynamics. Phys Chem Chem Phys 2022; 24:12346-12353. [PMID: 35546500 DOI: 10.1039/d2cp01056a] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Recent experimental work revealed that the lifetime of the S3 state of protonated 7-azaindole is about ten times longer than that of protonated 6-azaindole. We simulated the nonradiative decay pathways of these molecules using trajectory surface hopping dynamics after photoexcitation into S3 to elucidate the reason for this difference. Both isomers mainly follow a common ππ* relaxation pathway involving multiple state crossings while coming down from S3 to S1 in the subpicosecond time scale. However, the simulations reveal that the excited-state topographies are such that while the 6-isomer can easily access the region of nonadiabatic transitions, the internal conversion of the 7-isomer is delayed by a pre-Dewar bond formation with a boat conformation.
Collapse
Affiliation(s)
- Ritam Mansour
- Aix Marseille University, CNRS, ICR, Marseille, France.
| | | | - Max Pinheiro
- Aix Marseille University, CNRS, ICR, Marseille, France.
| | | | | | - Mario Barbatti
- Aix Marseille University, CNRS, ICR, Marseille, France. .,Institut Universitaire de France, 75231 Paris, France.
| |
Collapse
|
43
|
Lee IS, Min SK. Generalized Formulation of the Density Functional Tight Binding-Based Restricted Ensemble Kohn-Sham Method with Onsite Correction to Long-Range Correction. J Chem Theory Comput 2022; 18:3391-3409. [PMID: 35549266 DOI: 10.1021/acs.jctc.2c00037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a generalized formulation for the combination of the density functional tight binding (DFTB) approach and the state-interaction state-average spin-restricted ensemble-referenced Kohn-Sham (SI-SA-REKS or SSR) method by considering onsite correction (OC) as well as the long-range corrected (LC) functional. The OC contribution provides more accurate energies and analytic gradients for individual microstates, while the multireference character of the SSR provides the correct description for conical intersections. We benchmark the LC-OC-DFTB/SSR method against various DFTB calculation methods for excitation energies and conical intersection structures with π/π* or n/π* characters. Furthermore, we perform excited-state molecular dynamics simulations with a molecular rotary motor with variations of LC-OC-DFTB/SSR approaches. We show that the OC contribution to the LC functional is crucial to obtain the correct geometry of conical intersections.
Collapse
Affiliation(s)
- In Seong Lee
- Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulju-gun, Ulsan 44919, South Korea
| | - Seung Kyu Min
- Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulju-gun, Ulsan 44919, South Korea
| |
Collapse
|
44
|
Nag P, Vennapusa SR. Unraveling the sub-100 fs ESIPT in 5-hydroxychromone using surface hopping simulations. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2021.113767] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
45
|
|
46
|
Janicki MJ, Szabla R, Šponer J, Góra RW. Photoinduced water-chromophore electron transfer causes formation of guanosine photodamage. Phys Chem Chem Phys 2022; 24:8217-8224. [PMID: 35319053 DOI: 10.1039/d2cp00801g] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
UV-induced photolysis of aqueous guanine nucleosides produces 8-oxo-guanine and Fapy-guanine, which can induce various types of cellular malfunction. The mechanistic rationale underlying photodestructive processes of guanine nucleosides is still largely obscure. Here, we employ accurate quantum chemical calculations and demonstrate that an excited-state non-bonding interaction of guanosine and a water molecule facilitates the electron-driven proton transfer process from water to the chromophore fragment. This subsequently allows for the formation of a crucial intermediate, namely guanosine photohydrate. Further (photo)chemical reactions of this intermediate lead to the known products of guanine photodamage.
Collapse
Affiliation(s)
- Mikołaj J Janicki
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370, Wrocław, Poland.
| | - Rafał Szabla
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370, Wrocław, Poland.
| | - Jiří Šponer
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 61265 Brno, Czech Republic.,National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Robert W Góra
- Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370, Wrocław, Poland.
| |
Collapse
|
47
|
Song C. State-averaged CASSCF with polarizable continuum model for studying photoreactions in solvents: Energies, analytical nuclear gradients, and non-adiabatic couplings. J Chem Phys 2022; 156:104102. [DOI: 10.1063/5.0085855] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
This paper presents state-averaged complete active space self-consistent field in polarizable continuum model (PCM) for studies of photoreactions in solvents. The wavefunctions of the solute and the PCM surface charges of the solvent are optimized simultaneously such that the state-averaged free energy is variationally minimized. The method supports both fixed weights and dynamic weights where the weights are automatically adjusted based on the energy gaps. The corresponding analytical nuclear gradients and non-adiabatic couplings are also derived. Furthermore, we show how the new method can be entirely formulated in terms of seven basic operations, which allows the implementation to benefit from existing high-performance libraries on graphical processing units. Results demonstrating the accuracy and performance of the implementation are presented and discussed. We also apply the new method to the study of minimal conical intersection search and photoreaction energy pathways in solvents. Effects from the polarity of the solvents and different formulas of dynamic weights are compared and discussed.
Collapse
Affiliation(s)
- Chenchen Song
- Department of Chemistry, University of California Davis, Davis, California 95616, USA
| |
Collapse
|
48
|
Vandaele E, Mališ M, Luber S. The photodissociation of solvated cyclopropanone and its hydrate explored via non-adiabatic molecular dynamics using ΔSCF. Phys Chem Chem Phys 2022; 24:5669-5679. [PMID: 35179527 PMCID: PMC8890323 DOI: 10.1039/d1cp05187c] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The decay of cyclopropanone is a typical example of a photodecomposition process. Ethylene and carbon monoxide are formed following the excitation to the first singlet excited state through a symmetrical or asymmetrical pathway. The results obtained with non-adiabatic molecular dynamics (NAMD) using the delta self-consistent field (ΔSCF) method correspond well to previous experimental and multireference theoretical studies carried out in the gas phase. Moreover, this efficient methodology allows NAMD simulations of cyclopropanone in aqueous solution to be performed, which reveal analogue deactivation mechanisms, but a shorter lifetime and reduced photodissociation as compared to the gas-phase. The excited state dynamics of cyclopropanone hydrate, an enzyme inhibitor, in an aqueous environment are reported as well. Cyclopropanone hydrate strongly interacts with the surrounding solvent via the formation of hydrogen bonds. Excitation to the first singlet excited state shows an asymmetric pathway with cyclopropanone hydrate and propionic acid as the main photoproducts. The lifetime and photodissociation of cyclopropanone are reduced in aqueous solution, while the excitation of solvated cyclopropanone hydrate yields a range of photoproducts.![]()
Collapse
Affiliation(s)
- Eva Vandaele
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland.
| | - Momir Mališ
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland.
| | - Sandra Luber
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland.
| |
Collapse
|
49
|
Dicks L, Wales DJ. Elucidating the solution structure of the K-means cost function using energy landscape theory. J Chem Phys 2022; 156:054109. [DOI: 10.1063/5.0078793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- L. Dicks
- University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - D. J. Wales
- University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| |
Collapse
|
50
|
Aziz A, Sidat A, Talati P, Crespo-Otero R. Understanding the solid state luminescence and piezochromic properties in polymorphs of an anthracene derivative. Phys Chem Chem Phys 2022; 24:2832-2842. [PMID: 35050275 DOI: 10.1039/d1cp05192j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Luminescent molecular crystals have gained significant research interest for optoelectronic applications. However, fully understanding their structural and electronic relationships in the condensed phase and under external stimuli remains a significant challenge. Here, piezochromism in the molecular crystal 9,10-bis((E)-2-(pyridin-4-yl)vinyl)anthracene (BP4VA) is studied using a combination of density functional theory (DFT) and time-dependent TD-DFT. We investigate the effects that molecular packing and geometry have on the electronic and phonon structure and the excited state properties in this archetypal system. We find that the luminescence properties are red-shifted with the transition from a herringbone to a sheet packing arrangement. An almost continuous red-shift in the band gap is found with the application of an external pressure through the enhancement of π-π and CH-π interactions, and is a mechanism in fine tuning an emissive response. The analysis of the phonon structure of the molecular crystal suggests restriction of motion in the herringbone packing arrangement, with motion restricted at higher pressure. This is supported by the Huang-Rhys factors which show a decrease in the reorganisation energy with the application of pressure. Ultimately, a balance between the decrease in reorganisation energies and the increase in exciton coupling will determine whether nonradiative decay is enhanced or decreased with the increase in pressure in these systems.
Collapse
Affiliation(s)
- Alex Aziz
- Department of Chemistry, Queen Mary University of London, School of Physical and Chemical Sciences, Mile End Road, London, E1 4NS, UK.
| | - Amir Sidat
- Department of Chemistry, Queen Mary University of London, School of Physical and Chemical Sciences, Mile End Road, London, E1 4NS, UK.
| | - Priyesh Talati
- Department of Chemistry, Queen Mary University of London, School of Physical and Chemical Sciences, Mile End Road, London, E1 4NS, UK.
| | - Rachel Crespo-Otero
- Department of Chemistry, Queen Mary University of London, School of Physical and Chemical Sciences, Mile End Road, London, E1 4NS, UK.
| |
Collapse
|