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Chi HY, Xi GQ, Zhao XM, Qu SJ, Liu X, Ji Y, Song MX, Zhang YL, Qin ZK, Zhang HJ. Theoretical study on a series of Blue-Green Ir(III) complexes used in OLED. Mol Phys 2023. [DOI: 10.1080/00268976.2022.2157343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Affiliation(s)
- Hao-Yuan Chi
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
- Jilin Meteorological Observation and Protection Center, Jilin Meteorological Service, Changchun, People’s Republic of China
| | - Guo-Qing Xi
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
- Infovision Optoelectronics (Kunshan) Co., Ltd, Kunshan, People’s Republic of China
| | - Xue-Ming Zhao
- Jilin Meteorological Observation and Protection Center, Jilin Meteorological Service, Changchun, People’s Republic of China
| | - Shao-Jun Qu
- Jilin Meteorological Observation and Protection Center, Jilin Meteorological Service, Changchun, People’s Republic of China
| | - Xiang Liu
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Ye Ji
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Ming-Xing Song
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Yong-Ling Zhang
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Zheng-Kun Qin
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Hong-Jie Zhang
- State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, People’s Republic of China
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Li H, Huang L, Huang Z, Zhang L, Tang Y, Wang X, He Y, Liu Z. Improving the chemical stability of blue heteroleptic iridium emitter FIrpic in the lowest triplet state through ancillary ligand modification: a theoretical perspective. Phys Chem Chem Phys 2022; 24:9543-9550. [PMID: 35389412 DOI: 10.1039/d2cp00185c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
With the aim of providing a deeper understanding of the underlying degradation mechanisms associated with the lifetime of blue emitters during the decay process of blue PhOLEDs, quantum chemistry studies were performed to examine the chemical degradation mechanism of common sky blue emitter iridium(III)bis(4,6-di-fluorophenyl)-pyridinato-N,C2')picolinate (FIrpic) and its derivatives with density functional theory (DFT) calculations. For these Ir(III) emitters, the Ir-N1 bond between the ancillary ligand (picolinate) and central iridium will be broken by external light stimuli, which is followed by conversion from the initial emissive metal-to-ligand charge transfer (3MLCT) state to the non-emissive metal centered (3MC) state. The potential energy change for the photo-induced degradation path is then dominated by the energy levels of the 3MT and 3MC states, which are related to the triplet transition energy and the Ir-N1 bond strength, respectively. Thereby, the Ir-N1 bond dissociation in the lowest triplet state will be much harder to proceed if the S0 → T1 transition energy gets more energetically stable or the bond strength gets larger. It is believed that strategic modification of the ancillary ligand, especially by substitution of electron-donating groups at the para position of the pyridyl N atom or extension of the p-electron delocalization, is an effective and easy way to enhance the photochemical stability of the typical blue emitter FIrpic.
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Affiliation(s)
- Huifang Li
- College of Electromechanical Engineering, Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials, Qingdao University of Science & Technology, Qingdao, Shandong 266061, China.
| | - Luyan Huang
- College of Electromechanical Engineering, Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials, Qingdao University of Science & Technology, Qingdao, Shandong 266061, China.
| | - Zehua Huang
- College of Electromechanical Engineering, Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials, Qingdao University of Science & Technology, Qingdao, Shandong 266061, China.
| | - Lisheng Zhang
- College of Electromechanical Engineering, Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials, Qingdao University of Science & Technology, Qingdao, Shandong 266061, China.
| | - Yuanzheng Tang
- College of Electromechanical Engineering, Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials, Qingdao University of Science & Technology, Qingdao, Shandong 266061, China.
| | - Xiaojun Wang
- College of Electromechanical Engineering, Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials, Qingdao University of Science & Technology, Qingdao, Shandong 266061, China.
| | - Yan He
- College of Electromechanical Engineering, Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials, Qingdao University of Science & Technology, Qingdao, Shandong 266061, China.
| | - Zhiming Liu
- College of Electromechanical Engineering, Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials, Qingdao University of Science & Technology, Qingdao, Shandong 266061, China.
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Han D, Ji X, Zhao L, Pang C. Theoretical insight on electronic structure and photophysical properties of a series of cyclometalated iridium(III) complexes bearing the substituted phenylpyrazole with different electron-donating or electron-accepting groups. Photochem Photobiol Sci 2021; 20:1487-1495. [PMID: 34709594 DOI: 10.1007/s43630-021-00125-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 10/21/2021] [Indexed: 10/20/2022]
Abstract
By using the density functional theory (DFT) and time-dependent density functional theory (TDDFT), the electronic structure and photophysical properties of a series of cyclometalated iridium(III) complexes bearing the substituted phenylpyrazole have been theoretically investigated. All studied iridium(III) complexes have the distorted octahedral geometry with cis-C,C, cis-O,O, and trans-N,N chelate disposition. The lowest lying singlet → singlet absorptions of all studied iridium(III) complexes are respectively located at 405 nm, 387 nm, 382 nm, 370 nm, and 387 nm. The calculated emission wavelengths for all studied iridium(III) complexes are 654 nm, 513 nm, 506 nm, 505 nm and 499 nm, respectively. The calculated emission wavelength for complex 4 at the CAM-B3LYP level is in good agreement with the experimental value. From the theoretical results, it can be seen that the electron-donating substituent groups have the important effect on the electronic structure and photophysical properties of all studied iridium(III) complexes. We hope that this study can provide valuable guidance for the design of new phosphorescent organic light-emitting diodes (OLEDs) materials.
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Affiliation(s)
- Deming Han
- School of Life Science and Technology, Changchun University of Science and Technology, Changchun, 130022, People's Republic of China.,Jilin Provincial Science and Technology Innovation Center of Optical Materials and Chemistry, Changchun, 130022, People's Republic of China
| | - Xiaoqiang Ji
- School of Life Science and Technology, Changchun University of Science and Technology, Changchun, 130022, People's Republic of China
| | - Lihui Zhao
- School of Life Science and Technology, Changchun University of Science and Technology, Changchun, 130022, People's Republic of China
| | - Chunying Pang
- School of Life Science and Technology, Changchun University of Science and Technology, Changchun, 130022, People's Republic of China.
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Sun X, Gong H, Zhang Y, Tian Y, Zhang H, Bai F, Wang J, Zhong K, Kong C. Investigating phosphorescence capability of halogen-substituted metal-free organic molecules: A theoretical study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 255:119642. [PMID: 33794424 DOI: 10.1016/j.saa.2021.119642] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 02/19/2021] [Accepted: 02/24/2021] [Indexed: 06/12/2023]
Abstract
The radiative and non-radiative decay processes of five compounds are investigated through a comprehensive computational approach, for the aim of investigating the effect of different halogen substituents to the phosphorescent emission. Their optimal configurations at the ground (S0) and lowest triplet excited (T1) states are obtained and the calculated phosphorescent emission spectra are comparable with the experimental values. For 1,4-di(9H-carbazol-9-yl)benzene (PDCz), the electronic transition is between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), while for the four halides, the electronic transitions are attributed to several molecular orbitals. According to calculations, 9,9'-(2,5-diiodo-1,4-phenylene)bis(9H-carbazole) (PDICz) possesses the largest radiative decay rate constant (kr) and non-radiative decay rate constant (knr), which can be attributed to the strong spin-orbital coupling from the heavy iodine atom. However, the phosphorescent quantum efficiency (Φ) of PDICz is lower than that of 9,9'-(2,5-dibromo-1,4-phenylene)bis(9H-carbazole) (PDBCz), implying that a comprehensive consideration is necessary. Furthermore, by analyzing the vibrational mode, we have confirmed that the reorganization energies are also influenced by the different halogen atoms. While the dominated factor that determines the kr and knr comes from the spin-orbital coupling. We expect that our research findings will be beneficial to the newly designed organic phosphorescent materials in the future.
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Affiliation(s)
- Xiaofei Sun
- College of Food Science and Technology, College of Chemistry and Chemical Engineering, Bohai University, Food Safety Key Lab of Liaoning Province, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou 121013, China; International Joint Research Laboratory of Nano-Micro Architecture Chemistry, Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun 130023, China
| | - Huihui Gong
- College of Food Science and Technology, College of Chemistry and Chemical Engineering, Bohai University, Food Safety Key Lab of Liaoning Province, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou 121013, China
| | - Yuxi Zhang
- College of Food Science and Technology, College of Chemistry and Chemical Engineering, Bohai University, Food Safety Key Lab of Liaoning Province, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou 121013, China
| | - Yuxin Tian
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry, Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun 130023, China
| | - Hongxing Zhang
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry, Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun 130023, China
| | - Fuquan Bai
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry, Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun 130023, China
| | - Jian Wang
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry, Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun 130023, China
| | - Keli Zhong
- College of Food Science and Technology, College of Chemistry and Chemical Engineering, Bohai University, Food Safety Key Lab of Liaoning Province, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou 121013, China.
| | - Chuipeng Kong
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry, Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun 130023, China.
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Wang SP, Li Y, Zhang ZX, Zhang Y, Wang Y, Kong SM, Li HC, Jian W, Bai FQ, Zhang HX. Computational Studies on the Materials Combining Graphene Quantum Dots and Pt Complexes with Adjustable Luminescence Characteristics. Inorg Chem 2021; 60:1480-1490. [PMID: 33427451 DOI: 10.1021/acs.inorgchem.0c02772] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Graphene materials with particular properties are proved to be beneficial to photoelectric devices, but there are rare reports on a positive effect by graphene on emissive layer materials of organic light-emitting diodes (OLEDs) previously. On the basis of the latest important experiments, an OLED device with the aid of graphene quantum dots shows the dawn of their application for luminescent materials. The luminescence performance has been improved, but the understanding of the internal excited-state radiation mechanism of the material needs further study. In this work, the Pt(II)-coordinated graphene quantum dot coplanar structures with different shapes are studied theoretically in detail, and the results present the improvement in phosphorescence under the promoted radiative decay and suppressed nonradiative decay. This composite combines the advantages of transition metal complexes and graphene quantum dots and also exhibits excellent properties in the light absorption region and carrier transportation for the OLED. This comprehensive theoretical calculation research can provide a comprehensive basis of the material design in the future.
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Affiliation(s)
- Shi-Ping Wang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry and College of Chemistry, Jilin University, Changchun 130023, China
| | - Yuan Li
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry and College of Chemistry, Jilin University, Changchun 130023, China
| | - Zhi-Xiang Zhang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry and College of Chemistry, Jilin University, Changchun 130023, China
| | - Yu Zhang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry and College of Chemistry, Jilin University, Changchun 130023, China
| | - Yu Wang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry and College of Chemistry, Jilin University, Changchun 130023, China
| | - Si-Min Kong
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry and College of Chemistry, Jilin University, Changchun 130023, China
| | - Hui-Cong Li
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry and College of Chemistry, Jilin University, Changchun 130023, China
| | - Wei Jian
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry and College of Chemistry, Jilin University, Changchun 130023, China
| | - Fu-Quan Bai
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry and College of Chemistry, Jilin University, Changchun 130023, China.,Beijing National Laboratory for Molecular Sciences, Beijing 100190, China
| | - Hong-Xing Zhang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry and College of Chemistry, Jilin University, Changchun 130023, China
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Qin ZK, Chi HY, Xi GQ, Liu X, Song MX, Wang J, Zhang YL, Lü SQ, Zhang HJ. Density functional theory and time-dependent density functional study a series of iridium complexes with low-efficiency roll-off properties. Mol Phys 2020. [DOI: 10.1080/00268976.2020.1718229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Zheng-Kun Qin
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Hao-Yuan Chi
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Guo-Qing Xi
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Xiang Liu
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Ming-Xing Song
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Jia Wang
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Yong-Ling Zhang
- College of Information Technology, Jilin Normal University, Siping, People’s Republic of China
| | - Shi-Quan Lü
- College of Physics, Jilin Normal University, Siping, People’s Republic of China
| | - Hong-Jie Zhang
- State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, People’s Republic of China
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Lei Y, Guo H, Wang J, Jia R. Regulating vibrational modes to improve quantum efficiency: insights from theoretical calculations on iridium(iii) complexes bearing tridentate NCN and NNC chelates. Dalton Trans 2019; 48:5064-5071. [PMID: 30919842 DOI: 10.1039/c8dt04882g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
We reported a theoretical study on [(NCN)Ir(iii)(NNC)]+ tridentate Ir(iii) complexes for organic light-emitting diode (OLED) applications. With appropriate chemical modifications onto the NCN ligand of [(NCN)Ir(iii)(NNC)]+, several rotational and stretching vibration modes were weakened or even eliminated, resulting in a weaker vibrational coupling between the emissive state and the ground state, therefore slowing down the non-radiative decay process, ultimately improving the quantum efficiency. We hope that these theoretical studies and the semi-quantitative prediction on phosphorescence efficiency could provide inspiration for the design of highly efficient phosphorescent materials.
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Affiliation(s)
- Yuanqing Lei
- Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200438, P. R. China.
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Li Y, Fan XW, Chen J, Bai FQ, Zhang HX. Theoretical study on the excited state decay properties of iron(ii) polypyridine complexes substituted by bromine and chlorine. RSC Adv 2019; 9:31621-31627. [PMID: 35527963 PMCID: PMC9072724 DOI: 10.1039/c9ra06366h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 09/17/2019] [Indexed: 12/19/2022] Open
Abstract
Transition metal iron(ii) polypyridyl complexes with quintet ground states were deeply investigated by density functional theory (DFT) and time-dependent density functional theory (TDDFT). Compared with the parent complex [Fe(tpy)2]2+ (tpy = 2,2′:6′,2′′-terpyridine), the ground states of the complexes substituted by halogen atoms changed from singlet states to quintet states with rare high spin excited state lifetimes. The substituted complex [Fe(dbtpy)2]2+ (1) results in a high spin metal–ligand charge transfer lifetime of 17.4 ps, which is 1.4 ps longer than that of [Fe(dctpy)2]2+ (2) with the substitution of chlorine atoms. The reason for this is explored by a combination of electronic structures, absorption spectra, extended transition state coupled with natural orbitals for chemical valence (ETS-NOCV) studies and potential energy curves (PECs). The distortion of 1 in the angles and dihedrals of the ligands is slightly larger than that in 2, although the average metal–ligand bond lengths of the latter are larger. The twisted octahedron decreases the interactions between the d orbitals of iron(ii) and the n/π orbitals of the ligands. Compared with 2, the enlarged energy gaps among the different PECs of 1 and the increased energy crossing points caused by the larger distortion result in the increase of its excited state lifetime. The different pairwise orbital interaction contributions between the metal center and the ligands in their singlet states are qualitatively estimated by ETS-NOCV. The results show that the substitution of bromine atoms will decrease the electrostatic attraction between the metal and ligands but not significantly impact the orbital interactions. Transition metal iron(ii) halogen substituted polypyridyl complexes with quintet ground states were deeply investigated by density functional theory (DFT) and time-dependent density functional theory (TDDFT).![]()
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Affiliation(s)
- Yuan Li
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- Laboratory of Theoretical and Computational Chemistry
- Institute of Theoretical Chemistry
- Jilin University
- Changchun 130023
| | - Xue-Wen Fan
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- Laboratory of Theoretical and Computational Chemistry
- Institute of Theoretical Chemistry
- Jilin University
- Changchun 130023
| | - Jie Chen
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- Laboratory of Theoretical and Computational Chemistry
- Institute of Theoretical Chemistry
- Jilin University
- Changchun 130023
| | - Fu-Quan Bai
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- Laboratory of Theoretical and Computational Chemistry
- Institute of Theoretical Chemistry
- Jilin University
- Changchun 130023
| | - Hong-Xing Zhang
- International Joint Research Laboratory of Nano-Micro Architecture Chemistry
- Laboratory of Theoretical and Computational Chemistry
- Institute of Theoretical Chemistry
- Jilin University
- Changchun 130023
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