排序方式: 共有76条查询结果,搜索用时 15 毫秒
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Hao-Jung Chang Mykhailo V. Bondar Dr. Natalia Munera Dr. Sylvain David Dr. Olivier Maury Dr. Gerard Berginc Dr. Boris Le Guennic Dr. Denis Jacquemin Dr. Chantal Andraud Dr. David J. Hagan Dr. Eric W. Van Stryland 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(17):e202104072
The fast relaxation processes in the excited electronic states of functionalized aza-boron-dipyrromethene (aza-BODIPY) derivatives ( 1 – 4 ) were investigated in liquid media at room temperature, including the linear photophysical, photochemical, and nonlinear optical (NLO) properties. Optical gain was revealed for nonfluorescent derivatives 3 and 4 in the near infrared (NIR) spectral range under femtosecond excitation. The values of two-photon absorption (2PA) and excited-state absorption (ESA) cross-sections were obtained for 1–4 in dichloromethane using femtosecond Z-scans, and the role of bromine substituents in the molecular structures of 2 and 4 is discussed. The nature of the excited states involved in electronic transitions of these dyes was investigated using quantum-chemical TD-DFT calculations, and the obtained spectral parameters are in reasonable agreement with the experimental data. Significant 2PA (maxima cross-sections ∼2000 GM), and large ESA cross-sections ∼10−20 m2 of these new aza-BODIPY derivatives 1–4 along with their measured high photostability reveal their potential for photonic applications in general and optical limiting in particular. 相似文献
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Julien Massue Karima Benelhadj Siwar Chibani Boris Le Guennic Denis Jacquemin Pascal Retailleau Gilles Ulrich Raymond Ziessel 《Tetrahedron letters》2014
The multi-step synthesis, structural and optical properties of original luminescent borate complexes derived from 2-(2′-hydroxybenzofuran)benzoxazole (HBBO) are reported. Functionalization at position 3 of the benzofuran ring was readily achieved through an electrophilic cyclization key step followed by a Sonogashira cross-coupling reaction. The optical properties of the resulting boron difluoride dyes highlight different photophysical behaviors depending on the nature of the substitution at position 3 of the benzofuran core (tBu-phenylacetylene or NnBu2-phenylacetylene). The NnBu2-phenylacetylene moiety favors a sizeable intramolecular charge transfer as evidenced by a strong solvatochromism; a feature further confirmed by ab initio calculations. 相似文献
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Fox MA Le Guennic B Roberts RL Brue DA Yufit DS Howard JA Manca G Halet JF Hartl F Low PJ 《Journal of the American Chemical Society》2011,133(45):18433-18446
A series of bimetallic ruthenium complexes [{Ru(dppe)Cp*}(2)(μ-C≡CArC≡C)] featuring diethynylaromatic bridging ligands (Ar = 1,4-phenylene, 1,4-naphthylene, 9,10-anthrylene) have been prepared and some representative molecular structures determined. A combination of UV-vis-NIR and IR spectroelectrochemical methods and density functional theory (DFT) have been used to demonstrate that one-electron oxidation of compounds [{Ru(dppe)Cp*}(2)(μ-C≡CArC≡C)](HC≡CArC≡CH = 1,4-diethynylbenzene; 1,4-diethynyl-2,5-dimethoxybenzene; 1,4-diethynylnaphthalene; 9,10-diethynylanthracene) yields solutions containing radical cations that exhibit characteristics of both oxidation of the diethynylaromatic portion of the bridge, and a mixed-valence state. The simultaneous population of bridge-oxidized and mixed-valence states is likely related to a number of factors, including orientation of the plane of the aromatic portion of the bridging ligand with respect to the metal d-orbitals of appropriate π-symmetry. 相似文献
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Jonathan Mendy Dr. Anh Thy Bui Dr. Amandine Roux Jean-Christophe Mulatier Damien Curton Dr. Alain Duperray Dr. Alexei Grichine Dr. Yannick Guyot Dr. Sophie Brasselet Dr. François Riobé Dr. Chantal Andraud Dr. Boris Le Guennic Dr. Véronique Patinec Pr. Raphael Tripier Dr. Maryline Beyler Dr. Olivier Maury 《Chemphyschem》2020,21(10):1036-1043
Cationic lanthanide complexes are generally able to spontaneously internalize into living cells. Following our previous works based on a diMe-cyclen framework, a second generation of cationic water-soluble lanthanide complexes based on a constrained cross-bridged cyclam macrocycle functionalized with donor-π-conjugated picolinate antennas was prepared with europium(III) and ytterbium(III). Their spectroscopic properties were thoroughly investigated in various solvents and rationalized with the help of DFT calculations. A significant improvement was observed in the case of the Eu3+ complex, while the Yb3+ analogue conserved photophysical properties in aqueous solvent. Two-photon (2P) microscopy imaging experiments on living T24 human cancer cells confirmed the spontaneous internalization of the probes and images with good signal-to-noise ratio were obtained in the classic NIR-to-visible configuration with the Eu3+ luminescent bioprobe and in the NIR-to-NIR with the Yb3+ one. 相似文献
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Comparative Analysis of Conjugated Alkynyl Chromophore–Triazacyclononane Ligands for Sensitized Emission of Europium and Terbium
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Marine Soulié Frédéric Latzko Emmanuel Bourrier Dr. Virginie Placide Dr. Stephen J. Butler Dr. Robert Pal Dr. James W. Walton Dr. Patrice L. Baldeck Dr. Boris Le Guennic Dr. Chantal Andraud Dr. Jurriaan M. Zwier Dr. Laurent Lamarque Prof. David Parker Dr. Olivier Maury 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(28):8636-8646
A series of europium and terbium complexes based on a functionalized triazacyclononane carboxylate or phosphinate macrocyclic ligand is described. The influence of the anionic group, that is, carboxylate, methylphosphinate, or phenylphosphinate, on the photophysical properties was studied and rationalized on the basis of DFT calculated structures. The nature, number, and position of electron‐donating or electron‐withdrawing aryl substituents were varied systematically within the same phenylethynyl scaffold in order to optimize the brightness of the corresponding europium complexes and investigate their two‐photon absorption properties. Finally, the europium complexes were examined in cell‐imaging applications, and selected terbium complexes were studied as potential oxygen sensors. 相似文献
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Luca Münzfeld Milena Dahlen Adrian Hauser Nolwenn Mahieu Senthil Kumar Kuppusamy Jules Moutet Maxime Tricoire Ralf Köppe Léo La Droitte Olivier Cador Boris Le Guennic Grégory Nocton Eufemio Moreno-Pineda Mario Ruben Peter W. Roesky 《Angewandte Chemie (International ed. in English)》2023,62(18):e202218107
Solvation of [(CNT)Ln(η8-COT)] (Ln=La, Ce, Nd, Tb, Er; CNT=cyclononatetraenyl, i.e., C9H9−; COT=cyclooctatetraendiid, i.e., C8H82−) complexes with tetrahydrofuran (THF) gives rise to neutral [(η4-CNT)Ln(thf)2(η8-COT)] (Ln=La, Ce) and ionic [Ln(thf)x(η8-COT)][CNT] (x=4 (Ce, Nd, Tb), 3 (Er)) species in a solid-to-solid transformation. Due to the severe distortion of the ligand sphere upon solvation, these species act as switchable luminophores and single-molecule magnets. The desolvation of the coordinated solvents can be triggered by applying a dynamic vacuum, as well as a temperature gradient stimulus. Raman spectroscopic investigations revealed fast and fully reversible solvation and desolvation processes. Moreover, we also show that a Nd:YAG laser can induce the necessary temperature gradient for a self-sufficient switching process of the Ce(III) analogue in a spatially resolved manner. 相似文献
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Guennic BL Petit S Chastanet G Pilet G Luneau D Amor NB Robert V 《Inorganic chemistry》2008,47(2):572-577
We report the synthesis and structural and magnetic characterization of an original Cu(3) oxidase model. The Schiff base ligand used in the synthesis derives from condensation of acetylacetone with glycine amino acid. The K[Cu(3)(L)(3)(micro(3)-OH)].(H(2)O)(2) complex crystallizes at room temperature in the tetragonal P43212 space group with a = 20.540(3) A and c = 15.866(6) A and consists of triangular Cu(3) units. The magnetic behavior interpretation suggests the presence of spin frustration, which has been investigated by means of ab initio DDCI calculations. It is shown that the system should be viewed as a "ménage à trois" spin-coupled pattern mediated by a central hydroxo group, lifting the doublet degeneracy by approximately 8 cm-1. 相似文献
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Picot A Malvolti F Le Guennic B Baldeck PL Williams JA Andraud C Maury O 《Inorganic chemistry》2007,46(7):2659-2665
The synthesis of new chromophore-based pyridine-dicarboxamide ligands and related D3 symmetric europium(III) complexes is described. The photophysical properties of the ligands and the complexes were thoroughly investigated and interpreted on the basis of theoretical calculations (TD-DFT). Finally, the luminescence of Eu(III) was sensitized by two-photon absorption of the ligand, illustrating the two-photon antenna effect phenomenon. 相似文献