Method and system for simulating the luminescence properties of organic room-temperature phosphorescent molecules under aggregation

Abstract

The application provides an organic room-temperature phosphorescent molecule under an aggregate light-emitting performance simulation method and system, obtains a geometric structure, an electronic structure and an aggregate structure through an organic room-temperature phosphorescent molecule structure, carries out calculation on microstructures of exciton coupling, electro-phonon coupling and spin-orbit coupling of the organic room-temperature phosphorescent molecule, researches excited state dynamics of the organic room-temperature phosphorescent molecule according to the microstructures, explores an internal relationship between a molecular aggregate form and the excited state dynamics, realizes controllable construction from a molecular structure, an aggregate form to phosphorescent properties, and provides reliable theoretical guidance for design and research and development of high-performance organic room-temperature phosphorescent molecules.

Description

Technical Field

[0001] This invention belongs to the field of organic room temperature phosphorescent molecular materials technology, and particularly relates to a method and system for simulating the luminescence performance of organic room temperature phosphorescent molecules in aggregates. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Molecular structure design and aggregate behavior regulation play crucial roles in improving the performance of organic room-temperature phosphorescence (RTP). While various high-efficiency, color-tunable emission, and stimulus-responsive RTP materials have been synthesized and reported, the intrinsic relationship between molecular structure, aggregation morphology, and phosphorescence properties remains to be explored. Furthermore, the photophysical properties of RTP molecules, such as radiative rate, non-radiative rate, intersystem crossing rate, luminescence efficiency, and lifetime, are closely related to the excited-state characteristics of the molecules. Molecular structure can provide suitable prerequisites for optimizing RTP performance, while the rational regulation of aggregate behavior is key to achieving high-efficiency RTP. Molecular structure significantly influences aggregate behavior, and different aggregate behaviors can affect the molecular geometry and electronic structure, thereby affecting excited-state properties, especially for dual-emission phosphors. Numerous studies have confirmed that the luminescence properties of RTP molecules are system-dependent; even for the same molecule, the excited-state properties and phosphorescence properties exhibited by different aggregates, such as amorphous and polycrystalline states, vary considerably. Therefore, the behavior of large and complex aggregates cannot be understood by simply extrapolating the properties of individual RTP molecules. At each level of complexity, novel properties emerge. A comprehensive consideration of the influence of molecular structure and aggregate behavior on excited-state properties, especially on the excited-state energy release process of RTP molecules, is key to achieving efficient RTP emission. Currently, the luminescence mechanism of organic room-temperature phosphorescent molecules in aggregates is still unclear, making it particularly important to explore the intrinsic relationship between molecular aggregation morphology and its excited-state dynamics. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, this invention provides a method and system for simulating the luminescence performance of organic room-temperature phosphorescent molecules in aggregates. Based on the microstructure, the dynamics of organic room-temperature phosphorescent molecules in the excited state are studied, and the intrinsic relationship between molecular aggregation morphology and its excited state dynamics is explored, realizing the controllable construction from molecular structure and aggregation morphology to phosphorescence properties.

[0005] To achieve the above objectives, a first aspect of the present invention provides a method for simulating the luminescence properties of organic room-temperature phosphorescent molecules in aggregates, comprising:

[0006] Based on the structure of organic room-temperature phosphorescent molecules, we can obtain the molecular geometry, electronic structure, and aggregate structure.

[0007] A QM / MM calculation model was constructed based on the aggregate structure described above.

[0008] Vibrational information and exciton coupling energy are obtained through the QM / MM calculation model and the geometric and electronic structures.

[0009] Based on the obtained vibration information and electronic structure, the electron-phonon coupling coefficient, as well as the spin-orbit coupling coefficient between the singlet and triplet states, were calculated.

[0010] Based on the exciton coupling energy, spin-orbit coupling coefficient, and electron-phonon coupling coefficient, the excited-state decay rate parameters of organic room-temperature phosphorescent molecules in aggregates are calculated using the thermal vibrational correlation function, thus obtaining the excited-state dynamics process.

[0011] A second aspect of the present invention provides a system for simulating the luminescence properties of organic room-temperature phosphorescent molecules in aggregates, comprising:

[0012] Acquisition module: Acquires the geometric structure, electronic structure, and aggregate structure of organic room-temperature phosphorescent molecules;

[0013] Model building module: Build a QM / MM calculation model based on the aggregate structure;

[0014] First calculation module: Obtain vibrational information and exciton coupling energy through the QM / MM calculation model and the geometric and electronic structures;

[0015] The second calculation module calculates the electron-phonon coupling coefficient and the spin-orbit coupling coefficient between the singlet and triplet states based on the obtained vibration information and electronic structure.

[0016] Simulation module: Based on exciton coupling energy, spin-orbit coupling coefficient and electron-phonon coupling coefficient, the excited state decay rate parameters of organic room temperature phosphorescent molecules in aggregates are calculated using thermal vibrational correlation functions to obtain the excited state dynamics process.

[0017] A third aspect of the present invention provides a computer device comprising: a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the computer device is running, the processor communicates with the memory via the bus, and when the machine-readable instructions are executed by the processor, a method for simulating the luminescence performance of organic room-temperature phosphorescent molecules in aggregates is performed.

[0018] A fourth aspect of the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs a method for simulating the luminescence properties of organic room-temperature phosphorescent molecules in aggregates.

[0019] The above one or more technical solutions have the following beneficial effects:

[0020] In this invention, the geometric, electronic, and aggregate structures of organic room-temperature phosphorescent molecules are obtained through the structure of organic room-temperature phosphorescent molecules. The microstructures of exciton coupling, electron-phonon coupling, and spin-orbit coupling of organic room-temperature phosphorescent molecules are calculated. Based on the microstructures, the dynamics of organic room-temperature phosphorescent molecules in the excited state are studied, and the intrinsic relationship between molecular aggregation morphology and its excited-state dynamics is explored. This enables the controllable construction of molecular structure, aggregation morphology, and phosphorescent properties, providing reliable theoretical guidance for the design and development of high-performance organic room-temperature phosphorescent molecules.

[0021] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0022] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0023] Figure 1 This is a schematic diagram of a multi-scale simulation of the luminescence performance of organic room-temperature phosphorescent molecular aggregates in Embodiment 1 of the present invention;

[0024] Figure 2 This is a schematic diagram illustrating the transition from single-molecule science research to aggregate science research in Embodiment 1 of the present invention.

[0025] Figure 3 This is a schematic diagram of a multi-scale simulation scheme for studying molecular luminescence properties in Embodiment 1 of the present invention. Detailed Implementation

[0026] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0027] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.

[0028] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0029] Example 1

[0030] like Figure 1 As shown, this embodiment discloses a method for simulating the luminescence performance of organic room-temperature phosphorescent molecules in aggregates, including:

[0031] Based on the structure of organic room-temperature phosphorescent molecules, we can obtain the molecular geometry, electronic structure, and aggregate structure.

[0032] A QM / MM calculation model was constructed based on the aggregate structure described above.

[0033] Vibrational information and exciton coupling energy are obtained through the QM / MM calculation model and the geometric and electronic structures.

[0034] Based on the obtained vibration information and electronic structure, the electron-phonon coupling coefficient, as well as the spin-orbit coupling coefficient between the singlet and triplet states, were calculated.

[0035] Based on the exciton coupling energy, spin-orbit coupling coefficient, and electron-phonon coupling coefficient, the excited-state decay rate parameters of organic room-temperature phosphorescent molecules in aggregates are calculated using the thermal vibrational correlation function, thus obtaining the excited-state dynamics process.

[0036] like Figures 1-3 As shown, a multi-scale simulation calculation scheme was built to study the excited-state dynamics of single molecules to aggregates, and the excited-state energy release process of organic room-temperature phosphorescent molecules was systematically investigated. The relationship between molecular structure, aggregation morphology and luminescence properties was elucidated, and the controllable construction of the microstructure and macroscopic properties of organic room-temperature phosphorescent materials was realized.

[0037] In this embodiment, for organic single molecules, a suitable quantization method is used to perform self-consistent calculations to obtain geometric and electronic structure information under stable configurations.

[0038] The acquisition of single crystals or eutectic structures will primarily be accomplished using the CALYPSO program. The main steps are as follows:

[0039] Step 1-1: Using the symmetry confinement method and the interatomic distance confinement method, space group sampling with equal probability is performed to exclude high-energy structures on the potential energy surface and obtain the initial crystal structure;

[0040] Steps 1-2: Using the lattice equilibrium state constraint method, set convergence criteria, perform energy minimization, and optimize and screen the initial crystal structure;

[0041] Steps 1-3: Use the local version of the particle swarm optimization algorithm to perform structural evolution and obtain a stable crystal structure; for multi-configuration crystals, the global version of the particle swarm optimization algorithm is prone to premature convergence.

[0042] Furthermore, for obtaining pure or doped films with disordered stacking structures, GROMACS will be primarily used for relevant computational simulations. The main process is as follows:

[0043] Step 2-1: Construct a cubic box with a side length of 40 nm using PACKMOL, and randomly fill it with the RTP molecules under study as the initial thin film structure. The size of the box can be adjusted appropriately according to the type and number of molecules in the system, and the force field parameters can be adjusted by fitting the electrostatic potential charge.

[0044] Step 2-2: Set the system temperature to 600K and the pressure to 100bar, and perform an initial 5ns simulation to allow the molecular system to rapidly aggregate. Then, perform a 10ns simulation at 600K and 1bar, followed by a slow 5ns reduction of the temperature to 300K. Minimize the system energy by conducting quasi-static annealing simulations or periodic annealing simulations from high temperature and high pressure to ambient temperature and pressure.

[0045] Steps 2-3: Further, equilibrium phase simulation was performed at 300K and 1 bar for 20 ns. During the last 10 ns of the equilibrium phase, a snapshot was generated every 10 ps. A total of 1000 snapshots were selected for average statistical analysis to obtain representative thin film structures.

[0046] In this embodiment, the precise calculations of exciton coupling, electron-phonon coupling, and spin-orbit coupling are as follows:

[0047] First, aggregate structures represent both crystal structures and disordered stacking structures. ， By sampling aggregate structures appropriately, a QM / MM computational model is constructed. QM / MM calculations will be performed using either GAUSSIAN or a combination of Turboomole, Chemshell, and DL-POLY. QM calculations will be performed using GAUSSIAN or Turboomole, while MM calculations will be performed using DL-POLY. The interface program Chemshell will be used to achieve efficient docking calculations between QM and MM, thereby enabling self-consistent calculations of the ground and excited states of the molecules within the aggregates. Based on these calculations, representative dimers are selected using the IGMH method, and exciton coupling energies are calculated using NWChem. Based on the obtained electronic structure and vibrational frequencies, the electron-phonon coupling coefficient is calculated using DUSHIN. Simultaneously, the spin-orbit coupling coefficient between singlet and triplet states is calculated using Dalton, and the influence of relevant physical parameters on the luminescence properties of room-temperature phosphorescent molecules is predicted. First-principles calculations are performed using Gaussian software to obtain vibrational information. The four-point method or canonical mode analysis is used to compare structural differences, obtain recombination energies, and quantitatively calculate the magnitude of non-adiabatic coupling strength.

[0048] In this embodiment, a multi-scale simulation study of the excited-state energy release process is conducted:

[0049] Based on the previously obtained molecular geometry, electronic structure, and vibrational frequency information, the recombination energy is calculated, and then the excited-state decay rate parameters are calculated using the thermovibrational correlation function method. Based on the calculated decay rate parameters and the obtained energy level structure, a multi-level rate method is developed to study the exciton conversion process and excited-state dynamics. The influence of exciton dynamic evolution on the excited-state energy release process under multi-channel conditions is analyzed. By studying the excited-state dynamics, including radiative rate, non-radiative rate, intersystem crossing rate, reversal, intersystem crossing rate, potential surface crossover decay rate, and exciton dynamic evolution, the macroscopic physical properties of the RTP molecular system, such as color, efficiency, and lifetime, can be characterized. Key parameters affecting the triplet exciton dynamics are identified, and the influence of molecular structure and aggregation morphology on the excited-state energy release process is systematically analyzed. Theoretically, the excitation wavelength, phosphorescence efficiency, phosphorescence lifetime, and emission spectrum of organic room-temperature phosphorescent molecules are predicted, providing a reliable theoretical basis for experimental design and optimization of high-performance organic room-temperature phosphorescent molecules.

[0050] Example 2

[0051] The purpose of this embodiment is to provide a system for simulating the luminescence performance of organic room-temperature phosphorescent molecules in aggregates, including:

[0052] Acquisition module: Acquires the geometric structure, electronic structure, and aggregate structure of organic room-temperature phosphorescent molecules;

[0053] Model building module: Build a QM / MM calculation model based on the aggregate structure;

[0054] First calculation module: Obtain vibrational information and exciton coupling energy through the QM / MM calculation model and the geometric and electronic structures;

[0055] The second calculation module calculates the electron-phonon coupling coefficient and the spin-orbit coupling coefficient between the singlet and triplet states based on the obtained vibration information and electronic structure.

[0056] Simulation module: Based on exciton coupling energy, spin-orbit coupling coefficient and electron-phonon coupling coefficient, the excited state decay rate parameters of organic room temperature phosphorescent molecules in aggregates are calculated using thermal vibrational correlation functions to obtain the excited state dynamics process.

[0057] Example 3

[0058] The purpose of this embodiment is to provide a computing device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the above-described method.

[0059] Example 4

[0060] The purpose of this embodiment is to provide a computer-readable storage medium.

[0061] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, performs the steps of the above method.

[0062] The steps and methods involved in the apparatuses of Embodiments 2, 3, and 4 above correspond to those in Embodiment 1. For specific implementation details, please refer to the relevant description section of Embodiment 1. The term "computer-readable storage medium" should be understood as a single medium or multiple media including one or more instruction sets; it should also be understood as including any medium capable of storing, encoding, or carrying an instruction set for execution by a processor and enabling the processor to perform any of the methods in this invention.

[0063] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0064] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for simulating the luminescence properties of organic room-temperature phosphorescent molecules in aggregates, characterized in that, include: Based on the organic room-temperature phosphorescent molecule structure, the geometric structure, electronic structure, and aggregate structure of the molecule are obtained. The crystalline structure and disordered stacking structure are also obtained from the organic room-temperature phosphorescent molecule structure, resulting in the aggregate structure. The crystalline structure of the organic room-temperature phosphorescent molecule is obtained using the CALYPSO program. Specifically, the initial crystal structure is obtained by using symmetry confinement and interatomic distance confinement methods for space group sampling with equal probability. The initial crystal structure is then screened using lattice equilibrium state constraint methods for energy minimization. Finally, the screened initial crystal structure is evolved using a localized version of particle swarm optimization algorithm to obtain the final crystal structure. The disordered stacking structure of organic room-temperature phosphorescent molecules was obtained using GROMACS software. Specifically, a cubic box was constructed using PACKMOL, and organic room-temperature phosphorescent molecules were inserted into the cubic box as the initial thin film structure. The force field parameters were adjusted by fitting the electrostatic potential charge. The system energy was minimized through quasi-static annealing simulation from high temperature and high pressure to room temperature and pressure or periodic annealing simulation. Equilibrium phase simulation was performed, and equilibrium statistical analysis was conducted during the equilibrium stage to obtain the disordered stacking structure of the thin film. A QM / MM calculation model was constructed based on the aggregate structure. Vibrational information and exciton coupling energy were obtained through the QM / MM calculation model and the geometric and electronic structures. Representative dimers were selected using the IGMH method, and the exciton coupling energy was calculated using NWChem. Based on the obtained vibrational information and electronic structure, the electron-phonon coupling coefficient and the spin-orbit coupling coefficient between the singlet and triplet states are calculated. Based on the exciton coupling energy, spin-orbit coupling coefficient and electron-phonon coupling coefficient, the excited state decay rate parameters of organic room temperature phosphorescent molecules in aggregates are calculated using the thermal vibrational correlation function, and the excited state dynamics process is obtained.

2. The method for simulating the luminescence performance of organic room-temperature phosphorescent molecules in aggregates as described in claim 1, characterized in that, Based on the obtained electronic structure and vibration information, the electron-phonon coupling coefficient is calculated using DUSHIN.

3. The method for simulating the luminescence properties of organic room-temperature phosphorescent molecules in aggregates as described in claim 1, characterized in that, Based on the obtained electronic structure and vibration information, the spin-orbit coupling coefficient between the singlet and triplet states is calculated using Dalton.

4. A system for simulating the luminescence performance of organic room-temperature phosphorescent molecules in aggregates, characterized in that, include: Acquisition Module: Based on the organic room-temperature phosphorescent molecule structure, the module acquires the molecule's geometric structure, electronic structure, and aggregate structure. It also acquires the crystalline structure and disordered stacking structure from the organic room-temperature phosphorescent molecule structure to obtain the aggregate structure. The CALYPSO program is used to acquire the crystalline structure of the organic room-temperature phosphorescent molecule. Specifically, symmetry confinement and interatomic distance confinement methods are used for space group sampling with equal probability to obtain the initial crystal structure. The lattice equilibrium state constraint method is used for energy minimization to screen the initial crystal structure. Finally, a localized version of particle swarm optimization algorithm is used to evolve the screened initial crystal structure to obtain the final crystal structure. The disordered stacking structure of organic room-temperature phosphorescent molecules was obtained using GROMACS software. Specifically, a cubic box was constructed using PACKMOL, and organic room-temperature phosphorescent molecules were inserted into the cubic box as the initial thin film structure. The force field parameters were adjusted by fitting the electrostatic potential charge. The system energy was minimized through quasi-static annealing simulation from high temperature and high pressure to room temperature and pressure or periodic annealing simulation. Equilibrium phase simulation was performed, and equilibrium statistical analysis was conducted during the equilibrium stage to obtain the disordered stacking structure of the thin film. Model building module: Build a QM / MM calculation model based on the aggregate structure; First calculation module: Vibrational information and exciton coupling energy are obtained through the QM / MM calculation model and the geometric and electronic structures; representative dimers are selected using the IGMH method, and the exciton coupling energy is calculated using NWChem; The second calculation module calculates the electron-phonon coupling coefficient and the spin-orbit coupling coefficient between the singlet and triplet states based on the obtained vibration information and electronic structure. Simulation module: Based on exciton coupling energy, spin-orbit coupling coefficient and electron-phonon coupling coefficient, the excited state decay rate parameters of organic room temperature phosphorescent molecules in aggregates are calculated using thermal vibrational correlation functions to obtain the excited state dynamics process.

5. A computer device, characterized in that, include: The computer device includes a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the computer device is running, the processor communicates with the memory via the bus. When the machine-readable instructions are executed by the processor, they perform the method for simulating the luminescence performance of organic room-temperature phosphorescent molecules in aggregates as described in any one of claims 1 to 3.

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the method for simulating the luminescence performance of organic room-temperature phosphorescent molecules in aggregates as described in any one of claims 1 to 3.

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