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Wei F, Lai SL, Zhao S, Ng M, Chan MY, Yam VWW, Wong KMC. Ligand Mediated Luminescence Enhancement in Cyclometalated Rhodium(III) Complexes and Their Applications in Efficient Organic Light-Emitting Devices. J Am Chem Soc 2019; 141:12863-12871. [PMID: 31310721 DOI: 10.1021/jacs.9b06308] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A series of luminescent cyclometalated rhodium(III) complexes have been designed and prepared. The improved luminescence property is realized by the judicious choice of a strong σ-donor cyclometalating ligand with a lower-lying intraligand (IL) state that would raise the d-d excited state and introduction of a lower-lying emissive IL excited state. These complexes exhibit high thermal stability and considerable luminescence quantum yields as high as up to 0.65 in thin film, offering themselves as promising light-emitting materials in OLEDs. Respectable external quantum efficiencies of up to 12.2% and operational half-lifetimes of over 3000 h at 100 cd m-2 have been achieved. This work demonstrates a breakthrough as the first example of an efficient rhodium(III) emitter for OLED application and opens up a new avenue for diversifying the development of OLED materials with rhodium metal being utilized as phosphors.
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Affiliation(s)
- Fangfang Wei
- Department of Chemistry , Southern University of Science and Technology , 1088 Xueyuan Blvd. , Shenzhen 518055 , PR China
| | - Shiu-Lun Lai
- Institute of Molecular Functional Materials (Areas of Excellence Scheme, University Grants Committee, Hong Kong) and Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong , PR China
| | - Shunan Zhao
- Department of Chemistry , Southern University of Science and Technology , 1088 Xueyuan Blvd. , Shenzhen 518055 , PR China
| | - Maggie Ng
- Institute of Molecular Functional Materials (Areas of Excellence Scheme, University Grants Committee, Hong Kong) and Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong , PR China
| | - Mei-Yee Chan
- Institute of Molecular Functional Materials (Areas of Excellence Scheme, University Grants Committee, Hong Kong) and Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong , PR China
| | - Vivian Wing-Wah Yam
- Institute of Molecular Functional Materials (Areas of Excellence Scheme, University Grants Committee, Hong Kong) and Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong , PR China
| | - Keith Man-Chung Wong
- Department of Chemistry , Southern University of Science and Technology , 1088 Xueyuan Blvd. , Shenzhen 518055 , PR China
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Czerwieniec R, Leitl MJ, Homeier HH, Yersin H. Cu(I) complexes – Thermally activated delayed fluorescence. Photophysical approach and material design. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2016.06.016] [Citation(s) in RCA: 321] [Impact Index Per Article: 40.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Steffen A, Costuas K, Boucekkine A, Thibault MH, Beeby A, Batsanov AS, Charaf-Eddin A, Jacquemin D, Halet JF, Marder TB. Fluorescence in Rhoda- and Iridacyclopentadienes Neglecting the Spin–Orbit Coupling of the Heavy Atom: The Ligand Dominates. Inorg Chem 2014; 53:7055-69. [DOI: 10.1021/ic501115k] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Andreas Steffen
- Institut
für Anorganische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Karine Costuas
- Institut
des Sciences Chimiques de Rennes, UMR 6226 CNRS - Université de Rennes 1, 35042 Rennes Cedex, France
| | - Abdou Boucekkine
- Institut
des Sciences Chimiques de Rennes, UMR 6226 CNRS - Université de Rennes 1, 35042 Rennes Cedex, France
| | | | - Andrew Beeby
- Department
of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | - Andrei S. Batsanov
- Department
of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | - Azzam Charaf-Eddin
- CEISAM, UMR CNRS 6230, Université de Nantes, 2 rue de la
Houssinière, 44322 Nantes Cedex 3, France
| | - Denis Jacquemin
- CEISAM, UMR CNRS 6230, Université de Nantes, 2 rue de la
Houssinière, 44322 Nantes Cedex 3, France
- Institut Universitaire de France, 103 bd Saint-Michel, 75005 Paris Cedex 05, France
| | - Jean-François Halet
- Institut
des Sciences Chimiques de Rennes, UMR 6226 CNRS - Université de Rennes 1, 35042 Rennes Cedex, France
| | - Todd B. Marder
- Institut
für Anorganische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Department
of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
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Steffen A, Ward RM, Tay MG, Edkins RM, Seeler F, van Leeuwen M, Pålsson LO, Beeby A, Batsanov AS, Howard JAK, Marder TB. Regiospecific Formation and Unusual Optical Properties of 2,5-Bis(arylethynyl)rhodacyclopentadienes: A New Class of Luminescent Organometallics. Chemistry 2014; 20:3652-66. [DOI: 10.1002/chem.201304068] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Indexed: 11/11/2022]
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Minaev B, Baryshnikov G, Agren H. Principles of phosphorescent organic light emitting devices. Phys Chem Chem Phys 2014; 16:1719-58. [DOI: 10.1039/c3cp53806k] [Citation(s) in RCA: 345] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Yersin H. Triplet Emitters for OLED Applications. Mechanisms of Exciton Trapping and Control of Emission Properties. TRANSITION METAL AND RARE EARTH COMPOUNDS 2012. [DOI: 10.1007/b96858] [Citation(s) in RCA: 393] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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The triplet state of organo-transition metal compounds. Triplet harvesting and singlet harvesting for efficient OLEDs. Coord Chem Rev 2011. [DOI: 10.1016/j.ccr.2011.01.042] [Citation(s) in RCA: 952] [Impact Index Per Article: 73.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Organometallic Pt(II) and Ir(III) Triplet Emitters for OLED Applications and the Role of Spin–Orbit Coupling: A Study Based on High-Resolution Optical Spectroscopy. TOP ORGANOMETAL CHEM 2010. [DOI: 10.1007/3418_2009_6] [Citation(s) in RCA: 192] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Rausch AF, Murphy L, Williams JAG, Yersin H. Probing the Excited State Properties of the Highly Phosphorescent Pt(dpyb)Cl Compound by High-Resolution Optical Spectroscopy. Inorg Chem 2009; 48:11407-14. [DOI: 10.1021/ic901523u] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Andreas F. Rausch
- Universität Regensburg, Institut für Physikalische und Theoretische Chemie, 93053 Regensburg, Germany
| | - Lisa Murphy
- Department of Chemistry, University of Durham, Durham, DH1 3LE, U.K
| | | | - Hartmut Yersin
- Universität Regensburg, Institut für Physikalische und Theoretische Chemie, 93053 Regensburg, Germany
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Minaev B, Ågren H, Angelis FD. Theoretical design of phosphorescence parameters for organic electro-luminescence devices based on iridium complexes. Chem Phys 2009. [DOI: 10.1016/j.chemphys.2009.02.014] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Nozaki K, Takamori K, Nakatsugawa Y, Ohno T. Theoretical Studies of Phosphorescence Spectra of Tris(2,2‘-bipyridine) Transition Metal Compounds. Inorg Chem 2006; 45:6161-78. [PMID: 16878925 DOI: 10.1021/ic052068r] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Phosphorescence spectra of tris(2,2'-bipyridine) metal compounds, [M(bpy)3]n+, where M = Zn(II), Ru(II), Os(II), Rh(III), and Ir(III), were calculated using a harmonic oscillator approximation of adiabatic potential surfaces obtained by density functional theory (DFT). Using the Huang-Rhys (S) factors calculated by theoretical Franck-Condon analysis of T1 and S0 geometries, we successfully reproduced the emission spectra observed under various conditions by nonempirical calculations. The simulations of well-structured spectra of the Zn(II), Rh(III), and Ir(III) compounds confirmed that the emission originated from localized ligand-centered excited states with considerably distorted geometries of C2 symmetry. The spectrum simulation revealed that the phosphorescence state of [Ru(bpy)3]2+ was localized 3MLCT both in a solution and a glass matrix. Furthermore, a highly resolved phosphorescence spectrum observed for [Ru(bpy)3]2+ doped in a [Zn(bpy)3](ClO4)2 crystal was reproduced well using the geometry of the localized 3MLCT by assuming mode-specific broadening of low-frequency intramolecular vibrational modes. The deuterium effects of the electronic origins of the doped crystal observed by Riesen et al. were in excellent agreement with those predicted for the localized 3MLCT. However, the calculated satellite structures of the localized 3MLCT involving bpy-h8 in [Ru(bpy-h8)(3-x)(bpy-d8)x]2+ (x = 1,2) exhibited only the bpy-h8 vibrational modes, inconsistent with the simultaneous appearance of both bpy-h8 and bpy-h8 modes in the observed spectra. A simulation on the basis of the geometry of the delocalized 3MLCT was in reasonable agreement with an unresolved spectrum observed for a neat crystal of [Ru(bpy)3](PF6)2, which is inconsistent with the assignments of localized 3MLCT on the basis of the electronic origins. The inconsistency of the assignment on the basis of the adiabatic model is discussed in terms of vibronic coupling between the localized 3MLCT states. The 3MLCT state in [Os(bpy)3]2+ seems to vary with the environment: a fully localized 3MLCT in a solution, partially localized in a glass matrix, and delocalized in PF6 salts.
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Affiliation(s)
- Koichi Nozaki
- Department of Chemistry, Graduate School of Science, Osaka University, 1-16 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
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Albuquerque RQ, Popović Z, De Cola L, Calzaferri G. Luminescence Quenching by O2 of a Ru2+ Complex Attached to Zeolite L. Chemphyschem 2006; 7:1050-3. [PMID: 16625677 DOI: 10.1002/cphc.200600020] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Rodrigo Q Albuquerque
- Department of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
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Kenichi G, Hiroyuki S, Chihaya A. Phosphorescence Decay Mechanism of Ir(ppy)3 in a Solid Matrix. J PHOTOPOLYM SCI TEC 2005. [DOI: 10.2494/photopolymer.18.47] [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]
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14
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Energy transfer and harvesting in [Ru1−xOsx(bpy)3](PF6)2 and {Λ-[Ru(bpy)3]Δ-[Os(bpy)3]}(PF6)4. Coord Chem Rev 2002. [DOI: 10.1016/s0010-8545(02)00106-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Low-Lying Electronic States and Photophysical Properties of Organometallic Pd(II) and Pt(II) Compounds. Modern Research Trends Presented in Detailed Case Studies. TRANSITION METAL AND RARE EARTH COMPOUNDS 2001. [DOI: 10.1007/3-540-44474-2_3] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Excited State Spectroscopy and Excited State Dynamics of Rh(III) and Pd(II) Chelates as Studied by Optically Detected Magnetic Resonance Techniques. ACTA ACUST UNITED AC 2000. [DOI: 10.1007/3-540-44447-5_2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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18
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Yersin H, Strasser J. Triplets in metal–organic compounds. Chemical tunability of relaxation dynamics. Coord Chem Rev 2000. [DOI: 10.1016/s0010-8545(00)00326-x] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Yersin H, Donges D, Nagle JK, Sitters R, Glasbeek M. Intraligand charge transfer in the Pd(II) oxinate complex Pd(qol)2. Site-selective emission, excitation, and optically detected magnetic resonance. Inorg Chem 2000; 39:770-7. [PMID: 11272575 DOI: 10.1021/ic991023l] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The first spectroscopic investigation of Pd(qol)2 (qol- = 8-quinolinolato-N,O = oxinate) dissolved in an n-octane matrix (Shpol'skii matrix) is reported. Application of several spectroscopic methods at liquid helium temperatures (typically, T = 1.2 K), such as site-selective and highly resolved luminescence and excitation spectroscopy, time-resolved emission spectroscopy, optically detected magnetic resonance, microwave recovery, phosphorescence microwave double-resonance, and magnetic fields, allows us to characterize the lowest excited electronic states in detail. In accord with previous assignments for the related Pt(qol)2 it is shown that these lowest states represent-intraligand charge-transfer states, namely, 1ILCT and 3ILCT. The electronic origin of the 1ILCT state lies at 20,617 cm(-1) (site A). It exhibits a nearly homogeneous line width with a half-width of about 80 cm(-1) (fwhm), which corresponds to a lifetime of tau(1ILCT) approximately equals 2 x 10(-13) s. This value is even shorter than that found for Pt(qol)2, presumably due to intersystem crossings and relaxations to dd* states. The electronic origin of the 3ILCT state lies at 16 090 cm(-1) (site A), and its zero-field splittings (zfs) into three sublevels are 2E = 2356 MHz (0.0785 cm(-1)) and D - E = 5241 MHz (0.175 cm(-1)). The emission decay times of the three sublevels are determined as tauI = 90 +/- 30 ms, tau(II) = 180 +/- 10 mus, and tau(II) = 80 +/- 10 mus. (Slightly different values are found for a second site B at 16,167 cm(-1).) From the small values of zfs and the long emission decay times it is concluded that metal-d or MLCT admixtures to 3ILCT are very small. This result clearly reflects the ligand-centered character of the transition. The assignment as an ILCT transition is supported by the occurrence of relatively strong vibrational satellites of Pd-N and Pd-O character in highly resolved emission spectra. Although the transition is ascribed to a charge-transfer process, the geometry changes between the ground state and 3ILCT are very small. The results found for Pd(qol)2 are compared to those of companion studies of Pt(qol)2 and Pt(qtl)2 (qtl- = 8-quinolinethiolato-N,S).
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Affiliation(s)
- H Yersin
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, Germany
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Yersin H, Humbs W. Spatial Extensions of Excited States of Metal Complexes. Tunability by Chemical Variation. Inorg Chem 1999. [DOI: 10.1021/ic990582p] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hartmut Yersin
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, D-93040 Regensburg, Germany
| | - Werner Humbs
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, D-93040 Regensburg, Germany
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Keyes TE, O'Connor CM, O'Dwyer U, Coates CG, Callaghan P, McGarvey JJ, Vos JG. Isotope and Temperature Dependence of Dual Emission in a Mononuclear Ruthenium(II) Polypyridyl Compound. J Phys Chem A 1999. [DOI: 10.1021/jp991955a] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tia E. Keyes
- Inorganic Chemistry Research Centre, School of Chemical Sciences, Dublin City University, Dublin 9, Ireland, and School of Chemistry, Queen's University of Belfast, Belfast BT9 5AG, Northern Ireland
| | - Christine M. O'Connor
- Inorganic Chemistry Research Centre, School of Chemical Sciences, Dublin City University, Dublin 9, Ireland, and School of Chemistry, Queen's University of Belfast, Belfast BT9 5AG, Northern Ireland
| | - Una O'Dwyer
- Inorganic Chemistry Research Centre, School of Chemical Sciences, Dublin City University, Dublin 9, Ireland, and School of Chemistry, Queen's University of Belfast, Belfast BT9 5AG, Northern Ireland
| | - Colin G. Coates
- Inorganic Chemistry Research Centre, School of Chemical Sciences, Dublin City University, Dublin 9, Ireland, and School of Chemistry, Queen's University of Belfast, Belfast BT9 5AG, Northern Ireland
| | - Philip Callaghan
- Inorganic Chemistry Research Centre, School of Chemical Sciences, Dublin City University, Dublin 9, Ireland, and School of Chemistry, Queen's University of Belfast, Belfast BT9 5AG, Northern Ireland
| | - John J. McGarvey
- Inorganic Chemistry Research Centre, School of Chemical Sciences, Dublin City University, Dublin 9, Ireland, and School of Chemistry, Queen's University of Belfast, Belfast BT9 5AG, Northern Ireland
| | - Johannes G. Vos
- Inorganic Chemistry Research Centre, School of Chemical Sciences, Dublin City University, Dublin 9, Ireland, and School of Chemistry, Queen's University of Belfast, Belfast BT9 5AG, Northern Ireland
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Glasbeek M, Sitters R, van Veldhoven E, von Zelewsky A, Humbs W, Yersin H. Optically Detected Magnetic Resonance in the Lowest Triplet State of Pd(2-thpy)2. Inorg Chem 1998. [DOI: 10.1021/ic980251x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | - A. von Zelewsky
- Institut de Chimie Inorganique et Analytique, Université de Fribourg, CH-1700 Fribourg, Switzerland
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Ligand-centered 3ππ∗ emission and raman activity of [Pt(bpy-h8) (bpy-d8)2−]2+ (n=0,1,2). Inorganica Chim Acta 1997. [DOI: 10.1016/s0020-1693(97)05689-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Schmidt J, Strasser J, Yersin H. Determination of Relaxation Paths in the Manifold of Excited States of Pt(2-thpy)2 and [Ru(bpy)3]2+ by Time-Resolved Excitation and Emission. Inorg Chem 1997. [DOI: 10.1021/ic960565p] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Josef Schmidt
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, D-93040 Regensburg, Germany
| | - Johann Strasser
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, D-93040 Regensburg, Germany
| | - Hartmut Yersin
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, D-93040 Regensburg, Germany
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Donges D, Nagle JK, Yersin H. Intraligand Charge Transfer in Pt(qol)(2). Characterization of Electronic States by High-Resolution Shpol'skii Spectroscopy. Inorg Chem 1997; 36:3040-3048. [PMID: 11669955 DOI: 10.1021/ic9609463] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pt(qol)(2) (qol(-) = 8-quinolinolato-O,N) is investigated in the Shpol'skii matrices n-heptane, n-octane-h(18), n-octane-d(18), n-nonane, and n-decane, respectively. For the first time, highly resolved triplet phosphorescence as well as triplet and singlet excitation spectra are obtained at T = 1.2 K by site-selective spectroscopy. This permits the detailed characterization of the low-lying singlet and triplet states which are assigned to result mainly from intraligand charge transfer (ILCT) transitions. The electronic origin corresponding to the (3)ILCT lies at 15 426 cm(-)(1) (FWHM approximately 3 cm(-)(1)) exhibiting a zero-field splitting smaller than 1 cm(-)(1), which shows that the metal d-orbital contribution to the (3)ILCT is small. At T = 1.2 K, the three triplet sublevels emit independently due to slow spin-lattice relaxation (slr) processes. Therefore, the phosphorescence decays triexponentially with components of 4.5, 13, and 60 &mgr;s. Interestingly, two of the sublevels can be excited selectively, which leads to a distinct spin polarization manifested by a biexponential decay. At T = 20 K, the decay becomes monoexponential with tau = 10 &mgr;s due to a fast slr between the triplet sublevels. From the Zeeman splitting of the (3)ILCT the g-factor is determined to be 2.0 as expected for a relatively pure spin triplet. The (1)ILCT has its electronic origin at 18 767 cm(-)(1) and exhibits a homogeneous line width of about 12 cm(-)(1). This feature allows us to estimate a singlet-triplet intersystem crossing rate of about 2 x 10(12) s(-)(1). This relatively large rate compared to values found for closed shell metal M(qol)(n)() compounds displays the importance of spin-orbit coupling induced by the heavy metal ion. Moreover, this small admixture leads to the relatively short emission decay times. All spectra show highly resolved vibrational satellite structures. These patterns provide information about vibrational energies (which are in good accordance with Raman data) and shifts of equilibrium positions between ground and excited states. These shifts are different in the (1)ILCT and (3)ILCT states. The vibrational satellite structures support the assignment of ILCT character to the lowest excited states.
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Affiliation(s)
- Dirk Donges
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, D-93040 Regensburg, Germany, and Department of Chemistry, Bowdoin College, Brunswick, Maine 04011
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Low-lying electronic states of [Rh(bpy)3]3+, [Pt(bpy)2]2+, and [Ru(bpy)3]2+. A comparative study based on highly resolved and time-resolved spectra. Coord Chem Rev 1997. [DOI: 10.1016/s0010-8545(96)01318-5] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Characterization of excited electronic and vibronic states of platinum metal compounds with chelate ligands by highly frequency-resolved and time-resolved spectra. Top Curr Chem (Cham) 1997. [DOI: 10.1007/bfb0119213] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Riesen H, Wallace L, Krausz E. Localized (3)MLCT Excitations of [Ru(bpy)(3)(-)(x)()(bpy-6,6'-d(2))(x)()](2+) (x = 0-3) in [Zn(bpy)(3)](ClO(4))(2) (bpy = 2,2'-Bipyridine). Inorg Chem 1996; 35:6908-6909. [PMID: 11666862 DOI: 10.1021/ic960590v] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hans Riesen
- Research School of Chemistry, The Australian National University, Canberra, ACT 0200, Australia
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Riesen H, Wallace L, Krausz E. Localized 3MLCT Transitions in [Ru(bpy)3-x(bpy-6,6‘-d2)x]2+ (x = 0−3, bpy = 2,2‘-Bipyridine). Probing Minimally Perturbed Chromophores. ACTA ACUST UNITED AC 1996. [DOI: 10.1021/jp961792f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hans Riesen
- Research School of Chemistry, The Australian National University, Canberra, ACT 0200, Australia
| | - Lynne Wallace
- Research School of Chemistry, The Australian National University, Canberra, ACT 0200, Australia
| | - Elmars Krausz
- Research School of Chemistry, The Australian National University, Canberra, ACT 0200, Australia
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