1
|
Reddy SR, Coto PB, Thoss M. Intramolecular singlet fission: Quantum dynamical simulations including the effect of the laser field. J Chem Phys 2024; 160:194306. [PMID: 38767260 DOI: 10.1063/5.0209546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 04/30/2024] [Indexed: 05/22/2024] Open
Abstract
In the previous work [Reddy et al., J. Chem. Phys. 151, 044307 (2019)], we have analyzed the dynamics of the intramolecular singlet fission process in a series of prototypical pentacene-based dimers, where the pentacene monomers are covalently bonded to a phenylene linker in ortho, meta, and para positions. The results obtained were qualitatively consistent with the experimental data available, showing an ultrafast population of the multiexcitonic state that mainly takes place via a mediated (superexchange-like) mechanism involving charge transfer and doubly excited states. Our results also highlighted the instrumental role of molecular vibrations in the process as a sizable population of the multiexcitonic state could only be obtained through vibronic coupling. Here, we extend these studies and investigate the effect of the laser field on the dynamics of intramolecular singlet fission by explicitly including the coupling to the laser field in our model. In this manner, and by selectively tuning the laser field to the different low-lying absorption bands of the systems investigated, we analyze the wavelength dependence of the intramolecular singlet fission process. In addition, we have also analyzed how the nature of the initially photoexcited electronic state (either localized or delocalized) affects its dynamics. Altogether, our results provide new insights into the design of intramolecular singlet fission-active molecules.
Collapse
Affiliation(s)
- S Rajagopala Reddy
- Department of Chemistry, School of Chemical Sciences and Pharmacy, Central University of Rajasthan, NH-8, Bandarsindri, Ajmer, Rajasthan 305817, India
| | - Pedro B Coto
- Materials Physics Center (CFM), Spanish National Research Council (CSIC) and Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 5, 20018 Donostia-San Sebastián, Spain
| | - Michael Thoss
- Institute of Physics, Albert-Ludwigs University Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany
| |
Collapse
|
2
|
Zhang L, Wang SL, Tan Y, Tao GH, Yuan WL, Fu J, Zhang GH, He L, Tao G. Hydrogen-bonding and "π-π" interaction promoted solution-processable mixed matrix membranes for aromatic amines detection. JOURNAL OF HAZARDOUS MATERIALS 2022; 430:128490. [PMID: 35739671 DOI: 10.1016/j.jhazmat.2022.128490] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 01/30/2022] [Accepted: 02/12/2022] [Indexed: 06/15/2023]
Abstract
Detection of hazardous compounds can alleviate risk to human health. However, it remains a challenge to develop easy-to-use testing tools for carcinogenic aromatic amines. Herein, we presented a conjugated molecule-based aniline detector, mixed matrix membranes (MMMs), through the solution-processable strategy. The pentacene-based dispersed phase is achieved using the state-of-the-art ionic liquids (ILs) as the continuous phase, based on which MMMs are easily manufactured by a solution process. Moreover, molecular dynamics (MD) simulations and quantum mechanical calculations suggested that hydrogen bonding and π-π interaction between ILs cations and pentacene could promote the dissolution. These prepared MMMs can offer easy-operation and on-site detection of carcinogenic primary aromatic amines with eye-readable fluorescence signal. This work provides a paradigm for the design of a portable testing device for various hazardous compounds.
Collapse
Affiliation(s)
- Lei Zhang
- School of Advanced Materials, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Shuang-Long Wang
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
| | - Yunshu Tan
- School of Advanced Materials, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Guo-Hong Tao
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
| | - Wen-Li Yuan
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
| | - Jie Fu
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
| | - Guo-Hao Zhang
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
| | - Ling He
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China.
| | - Guohua Tao
- School of Advanced Materials, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
| |
Collapse
|
3
|
Mardazad S, Xu Y, Yang X, Grundner M, Schollwöck U, Ma H, Paeckel S. Quantum dynamics simulation of intramolecular singlet fission in covalently linked tetracene dimer. J Chem Phys 2021; 155:194101. [PMID: 34800955 DOI: 10.1063/5.0068292] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In this work, we study singlet fission in tetracene para-dimers, covalently linked by a phenyl group. In contrast to most previous studies, we account for the full quantum dynamics of the combined excitonic and vibrational system. For our simulations, we choose a numerically unbiased representation of the molecule's wave function, enabling us to compare with experiments, exhibiting good agreement. Having access to the full wave function allows us to study in detail the post-quench dynamics of the excitons. Here, one of our main findings is the identification of a time scale t0 ≈ 35 fs dominated by coherent dynamics. It is within this time scale that the larger fraction of the singlet fission yield is generated. We also report on a reduced number of phononic modes that play a crucial role in the energy transfer between excitonic and vibrational systems. Notably, the oscillation frequency of these modes coincides with the observed electronic coherence time t0. We extend our investigations by also studying the dependency of the dynamics on the excitonic energy levels that, for instance, can be experimentally tuned by means of the solvent polarity. Here, our findings indicate that the singlet fission yield can be doubled, while the electronic coherence time t0 is mainly unaffected.
Collapse
Affiliation(s)
- Sam Mardazad
- Department of Physics, Arnold Sommerfeld Center of Theoretical Physics, University of Munich, Theresienstrasse 37, 80333 Munich, Germany
| | - Yihe Xu
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Xuexiao Yang
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Martin Grundner
- Department of Physics, Arnold Sommerfeld Center of Theoretical Physics, University of Munich, Theresienstrasse 37, 80333 Munich, Germany
| | - Ulrich Schollwöck
- Department of Physics, Arnold Sommerfeld Center of Theoretical Physics, University of Munich, Theresienstrasse 37, 80333 Munich, Germany
| | - Haibo Ma
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Sebastian Paeckel
- Department of Physics, Arnold Sommerfeld Center of Theoretical Physics, University of Munich, Theresienstrasse 37, 80333 Munich, Germany
| |
Collapse
|
4
|
Hoche J, Flock M, Miao X, Philipp LN, Wenzel M, Fischer I, Mitric R. Excimer formation dynamics in the isolated tetracene dimer. Chem Sci 2021; 12:11965-11975. [PMID: 34667562 PMCID: PMC8457379 DOI: 10.1039/d1sc03214c] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 08/01/2021] [Indexed: 12/20/2022] Open
Abstract
The understanding of excimer formation and its interplay with the singlet-correlated triplet pair state 1(TT) is of high significance for the development of efficient organic electronics. Here, we study the photoinduced dynamics of the tetracene dimer in the gas phase by time-resolved photoionisation and photoion imaging experiments as well as nonadiabatic dynamics simulations in order to obtain mechanistic insight into the excimer formation dynamics. The experiments are performed using a picosecond laser system for excitation into the S2 state and reveal a biexponential time dependence. The time constants, obtained as a function of excess energy, lie in the range between ≈10 ps and 100 ps and are assigned to the relaxation of the excimer on the S1 surface and to its deactivation to the ground state. Simulations of the quantum-classical photodynamics are carried out in the frame of the semi-empirical CISD and TD-lc-DFTB methods. Both theoretical approaches reveal a dominating relaxation pathway that is characterised by the formation of a perfectly stacked excimer. TD-lc-DFTB simulations have also uncovered a second relaxation channel into a less stable dimer conformation in the S1 state. Both methods have consistently shown that the electronic and geometric relaxation to the excimer state is completed in less than 10 ps. The inclusion of doubly excited states in the CISD dynamics and their diabatisation further allowed to observe a transient population of the 1(TT) state, which, however, gets depopulated on a timescale of 8 ps, leading finally to the trapping in the excimer minimum. The understanding of excimer formation and its interplay with the singlet-correlated triplet pair state 1(TT) is of high significance for the development of efficient organic electronics.![]()
Collapse
Affiliation(s)
- Joscha Hoche
- Institut für Physikalische und Theoretische Chemie, Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Marco Flock
- Institut für Physikalische und Theoretische Chemie, Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Xincheng Miao
- Institut für Physikalische und Theoretische Chemie, Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Luca Nils Philipp
- Institut für Physikalische und Theoretische Chemie, Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Michael Wenzel
- Institut für Physikalische und Theoretische Chemie, Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Ingo Fischer
- Institut für Physikalische und Theoretische Chemie, Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Roland Mitric
- Institut für Physikalische und Theoretische Chemie, Universität Würzburg Am Hubland 97074 Würzburg Germany
| |
Collapse
|
5
|
Zeiser C, Moretti L, Reicherter F, Bettinger HF, Maiuri M, Cerullo G, Broch K. Singlet Fission in Dideuterated Tetracene and Pentacene. CHEMPHOTOCHEM 2021. [DOI: 10.1002/cptc.202000284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Clemens Zeiser
- Institute for Applied Physics University of Tübingen Auf der Morgenstelle 10 72076 Tübingen Germany
| | - Luca Moretti
- IFN-CNR Dipartimento di Fisica Politecnico di Milano Piazza Leonardo da Vinci 32 20133 Milan Italy
| | - Florian Reicherter
- Institute for Organic Chemistry University of Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Holger F. Bettinger
- Institute for Organic Chemistry University of Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Margherita Maiuri
- IFN-CNR Dipartimento di Fisica Politecnico di Milano Piazza Leonardo da Vinci 32 20133 Milan Italy
| | - Giulio Cerullo
- IFN-CNR Dipartimento di Fisica Politecnico di Milano Piazza Leonardo da Vinci 32 20133 Milan Italy
| | - Katharina Broch
- Institute for Applied Physics University of Tübingen Auf der Morgenstelle 10 72076 Tübingen Germany
| |
Collapse
|
6
|
Miyamoto H, Okada K, Tokuyama K, Nakano M. Theoretical Study on Singlet Fission Dynamics in Slip-Stack-like Pentacene Ring-Shaped Aggregate Models. J Phys Chem A 2021; 125:5585-5600. [PMID: 34142826 DOI: 10.1021/acs.jpca.1c03934] [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
We investigate the singlet fission (SF) dynamics of a slip-stack-like pentacene ring-shaped aggregate model, which is constructed by rotating each pentacene unit around its longitudinal axis in an H-aggregate ring. The aggregate size (N) and rotation angle (α) dependences of SF rates and double triplet (TT) yields are clarified using the quantum master equation method. It is found that there exist optimal ranges of the rotation angle α for each N, yielding efficient SF with high SF rates and TT yields. For example, in an 8-mer model, SF rates at α = 23 and 43° are 18.9 and 38.6 times as high as that at α = 30°, respectively, and the TT yields are as high as 0.871, 0.988, and 0.882 at α = 23, 30, and 43°, respectively. Analysis of the relative relaxation factors shows that the many-to-many relaxation paths from adiabatic Frenkel exciton (FE)-like states to TT-like states are opened by tuning α at relevant aggregate sizes, causing fast and high-TT-yield SF, and efficient SF occurs at α = 40° for medium N (7 ≤ N ≤ 10) or at α = 30° for large N (>10). This mechanism is interpreted by the second-order perturbation theory for electronic couplings. Namely, the inequality in the energies of charge-transfer states [CA and AC states, where the cation (C) and anion (A) are located at two neighboring sites in anticlockwise and clockwise directions, respectively] and the change in the amplitude and sign of the couplings between the FE, CT, and TT states are found to cause quantum superposition of the FE and TT states, which contribute to the high TT yield and SF rate. The present results contribute to a deeper understanding of SF dynamics in ring-shaped aggregates as well as to the development of their new design guidelines.
Collapse
Affiliation(s)
- Hajime Miyamoto
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Kenji Okada
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Kazuaki Tokuyama
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Masayoshi Nakano
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.,Center for Spintronics Research Network (CSRN), Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.,Center for Quantum Information and Quantum Biology (QIQB), Osaka University, Toyonaka Osaka 560-8531, Japan.,Innovative Catalysis Science Division (ICS), Institute for Open and Transdisciplinary Research Initiatives (OTRI), Osaka University, Toyonaka, Osaka 560-8531, Japan.,Research Center for Solar Energy Chemistry (RCSEC), Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| |
Collapse
|
7
|
Tan Y, Tao G. Exploring the State Space Structure of Multiple Spins via Modular Tensor Diagram Approach: Going beyond the Exciton Pair State. J Phys Chem A 2021; 125:1972-1980. [PMID: 33648334 DOI: 10.1021/acs.jpca.0c07832] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Fully understanding of multistate quantum systems could become formidable if not impossible as the system dimensionality increases. One ideal strategy to comprehend complex systems is to transform the system representation into a more structural one so that major characteristics, connections, and even underlying mechanisms can stand out from the huge unstructured information, e.g., the construction of spin eigenfunctions for a system of multiple spins through the diagonalization of the system Hamiltonian matrix. Here, instead of direct matrix diagonalization, the recently developed modular tensor diagram approach is applied to reorganize the state space structure of multispin systems, extending previous investigations on exciton pair states to exciton trimer states. This implementation demonstrates that the proposed approach not only provides a systematical way to transform the high dimensional multistate system into a well organized structure based on basic (exciton) modules but also paves the way to further analysis on potential applications. For example, the analysis on the state space of the exciton trimer system suggests a possible scheme to improve the laser performance via single fission involving multiexcitations and/or multiple fission steps.
Collapse
Affiliation(s)
- Yunshu Tan
- School of Advanced Materials, Peking University Shenzhen Graduate School, Shenzhen 518055, China.,Shenzhen Key Laboratory of New Energy Materials by Design, Peking University, Shenzhen 518055, China
| | - Guohua Tao
- School of Advanced Materials, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| |
Collapse
|
8
|
C A Valente D, do Casal MT, Barbatti M, Niehaus TA, Aquino AJA, Lischka H, Cardozo TM. Excitonic and charge transfer interactions in tetracene stacked and T-shaped dimers. J Chem Phys 2021; 154:044306. [PMID: 33514084 DOI: 10.1063/5.0033272] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Extended quantum chemical calculations were performed for the tetracene dimer to provide benchmark results, analyze the excimer survival process, and explore the possibility of using long-range-corrected (LC) time-dependent second-order density functional tight-biding (DFTB2) for this system. Ground- and first-excited-state optimized geometries, vertical excitations at relevant minima, and intermonomer displacement potential energy curves (PECs) were calculated for these purposes. Ground-state geometries were optimized with the scaled-opposite-spin (SOS) second-order Møller-Plesset perturbation (MP2) theory and LC-DFT (density functional theory) and LC-DFTB2 levels. Excited-state geometries were optimized with SOS-ADC(2) (algebraic diagrammatic construction to second-order) and the time-dependent approaches for the latter two methods. Vertical excitations and PECs were compared to multireference configuration interaction DFT (DFT/MRCI). All methods predict the lowest-energy S0 conformer to have monomers parallel and rotated relative to each other and the lowest S1 conformer to be of a displaced-stacked type. LC-DFTB2, however, presents some relevant differences regarding other conformers for S0. Despite some state-order inversions, overall good agreement between methods was observed in the spectral shape, state character, and PECs. Nevertheless, DFT/MRCI predicts that the S1 state should acquire a doubly excited-state character relevant to the excimer survival process and, therefore, cannot be completely described by the single reference methods used in this work. PECs also revealed an interesting relation between dissociation energies and the intermonomer charge-transfer interactions for some states.
Collapse
Affiliation(s)
- Daniel C A Valente
- Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | - Thomas A Niehaus
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622 Villeurbanne, France
| | - Adelia J A Aquino
- Department of Mechanical Engineering, Texas Tech University, Lubbock, Texas 79409, USA
| | - Hans Lischka
- School of Pharmaceutical Sciences and Technology, Tianjin University, Tianjin, People's Republic of China
| | - Thiago M Cardozo
- Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| |
Collapse
|
9
|
Alipour M, Safari Z. Singlet fission relevant energetics from optimally tuned range-separated hybrids. Phys Chem Chem Phys 2020; 22:27060-27076. [PMID: 33215617 DOI: 10.1039/d0cp03951a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
As a promising idea to design high-efficiency organic photovoltaics, singlet fission (SF) mechanism, i.e., generating two triplet excitons out of a single photon absorption, has recently come into the spotlight. Even though much effort has been devoted to this arena, accurately accounting for the SF process from the theoretical perspective has proven to be challenging. Herein, the SF energetics have thoroughly been investigated with the help of optimally tuned range-separated hybrid functionals (OT-RSHs) in both gas and solvent phases. Taking a series of experimentally known SF chromophores as working models, we have proposed and validated several variants of OT-RSH approximations for the reliable prediction of the energy levels which match the crucial criteria for the SF process, namely, the negative singlet-triplet and triplet-triplet energy gaps. We scrutinize the role of the OT-RSH ingredients, i.e., the underlying density functional approximations, short- and long-range exact-like exchange, as well as the range-separation parameter, for our purpose. The newly designed OT-RSHs outperform the standard RSHs and other related schemes such as screened-exchange approximations as well as other density functionals from different rungs for describing the SF energetics. More importantly, it is unveiled that although the OT-RSH coupled with the polarizable continuum model, OT-RSH-PCM, as well as the screened versions, OT-SRSHs, which account for the screening effect by the electron correlation through the scalar dielectric constant have some advantages over gas-phase computations using OT-RSHs, the energetics criteria of the SF process may not necessarily be satisfied. This in turn corroborates the idea of performing both the optimal tuning procedure and subsequent computations of the SF relevant energetics using OT-RSHs as a more reliable and affordable framework, at least for the present purpose. The applicability of the proposed models is also put into broader perspective, where they are used for the computational design of several chromophores as promising candidates prone to utilization in the SF-based materials. Hopefully, our recommended OT-RSHs can function as efficient models for both the theoretical modeling of SF chromophores and confirming the experimental observations in the field.
Collapse
Affiliation(s)
- Mojtaba Alipour
- Department of Chemistry, School of Science, Shiraz University, Shiraz 71946-84795, Iran.
| | | |
Collapse
|
10
|
Lubert-Perquel D, Szumska AA, Azzouzi M, Salvadori E, Ruloff S, Kay CMW, Nelson J, Heutz S. Structure Dependence of Kinetic and Thermodynamic Parameters in Singlet Fission Processes. J Phys Chem Lett 2020; 11:9557-9565. [PMID: 33119322 DOI: 10.1021/acs.jpclett.0c02505] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Singlet fission-whereby one absorbed photon generates two coupled triplet excitons-is a key process for increasing the efficiency of optoelectronic devices by overcoming the Shockley-Queisser limit. A crucial parameter is the rate of dissociation of the coupled triplets, as this limits the number of free triplets subsequently available for harvesting and ultimately the overall efficiency of the device. Here we present an analysis of the thermodynamic and kinetic parameters for this process in parallel and herringbone dimers measured by electron paramagnetic resonance spectroscopy in coevaporated films of pentacene in p-terphenyl. The rate of dissociation is higher for parallel dimers than for their herringbone counterparts, as is the rate of recombination to the ground state. DFT calculations, which provide the magnitude of the electronic coupling as well as the distribution of molecular orbitals for each geometry, suggest that weaker triplet coupling in the parallel dimer is the driving force for faster dissociation. Conversely, localization of the molecular orbitals and a stronger triplet-triplet interaction result in slower dissociation and recombination. The identification and understanding of how the intermolecular geometry promotes efficient triplet dissociation provide the basis for control of triplet coupling and thereby the optimization of one important parameter of device performance.
Collapse
Affiliation(s)
- Daphné Lubert-Perquel
- London Centre for Nanotechnology and Department of Materials, Imperial College London, Prince Consort Road, London SW7 2BP, U.K
| | - Anna A Szumska
- Department of Physics, Imperial College London, Prince Consort Road, London SW7 2BP, U.K
| | - Mohammed Azzouzi
- Department of Physics, Imperial College London, Prince Consort Road, London SW7 2BP, U.K
| | - Enrico Salvadori
- Department of Chemistry, University of Turin, Via Giuria 7, Turin 10125, Italy
| | - Stefan Ruloff
- Department of Chemistry, University of Saarland, Saarbrücken 66123, Germany
| | - Christopher M W Kay
- Department of Chemistry, University of Saarland, Saarbrücken 66123, Germany
- London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH, U.K
| | - Jenny Nelson
- Department of Physics, Imperial College London, Prince Consort Road, London SW7 2BP, U.K
| | - Sandrine Heutz
- London Centre for Nanotechnology and Department of Materials, Imperial College London, Prince Consort Road, London SW7 2BP, U.K
| |
Collapse
|
11
|
Affiliation(s)
- David R Reichman
- Department of Chemistry, Columbia University, New York, New York 10027, USA
| | - Xiaoyang Zhu
- Department of Chemistry, Columbia University, New York, New York 10027, USA
| |
Collapse
|
12
|
Yoshida T, Watanabe K, Petrović M, Kralj M. Anomalous Temperature Dependence of Exciton Spectral Diffusion in Tetracene Thin Film. J Phys Chem Lett 2020; 11:5248-5254. [PMID: 32551650 DOI: 10.1021/acs.jpclett.0c01537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this work, an ultrafast spectral diffusion of the lowest exciton in a tetracene ultrathin film is studied by two-dimensional electronic spectroscopy. From the analysis of the nodal line slope, the frequency-fluctuation correlation function (FFCF) of the exciton band is extracted. The FFCF contains two components with decay times of 400 and 80 fs; while the former can be understood by a linear exciton-phonon coupling model, the latter shows an order of magnitude increase in its amplitude from 96 to 186 K that cannot be explained by the same model. A novel scheme of the energy-gap fluctuations is examined, in which an intramolecular high-frequency mode causes the spectral diffusion that is enhanced through an anharmonic coupling to low-frequency phonon modes. This finding provides a valuable input for future theoretical predictions on the ultrafast nonadiabatic dynamics of the molecular exciton.
Collapse
Affiliation(s)
- Tatsuya Yoshida
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Kazuya Watanabe
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Marin Petrović
- Center of Excellence for Advanced Materials and Sensing Devices, Institute of Physics, Bijenic̆ka 46, 10000 Zagreb, Croatia
| | - Marko Kralj
- Center of Excellence for Advanced Materials and Sensing Devices, Institute of Physics, Bijenic̆ka 46, 10000 Zagreb, Croatia
| |
Collapse
|
13
|
Tao G, Tan Y. Modular Tensor Diagram Approach for the Construction of Spin Eigenfunctions: The Case Study of Exciton Pair States. J Phys Chem A 2020; 124:5435-5443. [PMID: 32551608 DOI: 10.1021/acs.jpca.0c00263] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Mapping out the high-dimensional state space would be valuable for better understanding the multistate quantum systems. Here, we demonstrate that high-dimensional spin state space can be mapped onto a tensor diagram in full dimension or self-similarly onto the reduced base state space. Based on the tensor diagram, a modular approach is proposed to construct spin eigenfunctions taking the basis of the lower-dimensional space as modules. The implementation of the approach on exciton pair states results in 16 spin eigenstates including 2 singlet states, 3 triplet states, and 1 quintet state with proper symmetry, in contrast to the ones generated using the conventional branching diagram method. The corresponding state energies obtained show the order of spin eigenstates reverses with respect to spin multiplicity. Interestingly, the state space can be decomposed into three subspaces corresponding to the singlet-singlet pair, singlet-triplet pair, and triplet-triplet pair, resulting in a modular structure that is invariant as intermolecular interactions diminish. The proposed approach offers a new perspective on the state space structure of multiple spin states, featuring a hierarchical symmetry, which could be extended to general high-dimensional quantum multistate systems.
Collapse
Affiliation(s)
- Guohua Tao
- School of Advanced Materials, Peking University Shenzhen Graduate School, Shenzhen 518055, China.,Shenzhen Key Laboratory of New Energy Materials by Design, Peking University, Shenzhen 518055, China
| | - Yunshu Tan
- School of Advanced Materials, Peking University Shenzhen Graduate School, Shenzhen 518055, China.,Shenzhen Key Laboratory of New Energy Materials by Design, Peking University, Shenzhen 518055, China
| |
Collapse
|
14
|
Tao G. Topology of quantum coherence in singlet fission: Mapping out spin micro-states in quasi-classical nonadiabatic simulations. J Chem Phys 2020; 152:074305. [DOI: 10.1063/1.5139538] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Guohua Tao
- School of Advanced Materials, Peking University Shenzhen Graduate School, Shenzhen 518055, China and Shenzhen Key Laboratory of New Energy Materials by Design, Peking University, Shenzhen 518055, China
| |
Collapse
|
15
|
Tao G. Topology of quantum coherence networks in singlet fission: mapping exciton states into real space and the dislocation induced three dimensional manifolds. Phys Chem Chem Phys 2020; 22:1258-1267. [PMID: 31850461 DOI: 10.1039/c9cp05102c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
An understanding of the global structure of quantum coherence networks in coupled multistate systems is of great importance for the development of emerging quantum technologies such as quantum control and quantum materials design. Here, we study the topology of a quantum coherence network of a typical singlet exciton fission system by mapping the exciton states into crystal structures in real space. The defects in crystals could lead to changes in the topological structures, and also fission dynamics. In particular, we demonstrate that the dislocation induced three dimensional manifold, which differs from its lower dimensional counterparts globally, could generate exotic global structures, such as chiral spirals, and modulate singlet fission substantially. The findings may shed light on the new possibilities of engineering effective structures for fission materials.
Collapse
Affiliation(s)
- Guohua Tao
- School of Advanced Materials, Peking University Shenzhen Graduate School, Shenzhen, 518055, China. and Shenzhen Key Laboratory of New Energy Materials by Design, Peking University, Shenzhen, 518055, China
| |
Collapse
|