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Готові списки джерел за темами / Circularly Polarized Luminescence (CPL)

Добірка наукової літератури з теми "Circularly Polarized Luminescence (CPL)"

Автор: Grafiati

Опубліковано: 22 червня 2023

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Статті в журналах з теми "Circularly Polarized Luminescence (CPL)":

1

Imai, Yoshitane. "Generation of Circularly Polarized Luminescence by Symmetry Breaking." Symmetry 12, no. 11 (October 28, 2020): 1786. http://dx.doi.org/10.3390/sym12111786.

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Circularly polarized luminescence (CPL) has attracted significant attention in the fields of chiral photonic science and optoelectronic materials science. In a CPL-emitting system, a chiral luminophore derived from chiral molecules is usually essential. In this review, three non-classical CPL (NC-CPL) systems that do not use enantiomerically pure molecules are reported: (i) supramolecular organic luminophores composed of achiral organic molecules that can emit CPL without the use of any chiral auxiliaries, (ii) achiral or racemic luminophores that can emit magnetic CPL (MCPL) by applying an external magnetic field of 1.6 T, and (iii) circular dichroism-silent organic luminophores that can emit CPL in the photoexcited state as a cryptochiral CPL system.

2

Song, Fengyan, Zheng Zhao, Zhiyang Liu, Jacky W. Y. Lam, and Ben Zhong Tang. "Circularly polarized luminescence from AIEgens." Journal of Materials Chemistry C 8, no. 10 (2020): 3284–301. http://dx.doi.org/10.1039/c9tc07022b.

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3

Kumar, Jatish, Tsuyoshi Kawai, and Takuya Nakashima. "Circularly polarized luminescence in chiral silver nanoclusters." Chemical Communications 53, no. 7 (2017): 1269–72. http://dx.doi.org/10.1039/c6cc09476g.

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Sets of mirror image circular dichroism (CD) and circularly polarized luminescence (CPL) spectra are for the first time demonstrated using enantiomeric dihydrolipoic acid (DHLA)-capped silver nanoclusters.

4

Imagawa, Takuro, Shuzo Hirata, Kenro Totani, Toshiyuki Watanabe, and Martin Vacha. "Thermally activated delayed fluorescence with circularly polarized luminescence characteristics." Chemical Communications 51, no. 68 (2015): 13268–71. http://dx.doi.org/10.1039/c5cc04105h.

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A metal-free aromatic compound exhibiting thermally activated delayed fluorescence as well as circularly polarized luminescence (CPL) with dissymmetry factors of 10⁻³ is reported. This compound shows a sign inversion between its circular dichroism signal and CPL, which is caused by a large conformational change upon photoexcitation.

5

Zou, Chen, Dan Qu, Haijing Jiang, Di Lu, Xiaoting Ma, Ziyi Zhao, and Yan Xu. "Bacterial Cellulose: A Versatile Chiral Host for Circularly Polarized Luminescence." Molecules 24, no. 6 (March 13, 2019): 1008. http://dx.doi.org/10.3390/molecules24061008.

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Materials capable of circularly polarized luminescence (CPL) have attracted considerable attention for their promising potential applications. Bacterial cellulose (BC) was characterized as having a stable right-handed twist, which makes it a potential chiral host to endow luminophores with CPL. Then, the CPL-active BC composite film was constructed by simply impregnating bacterial cellulose pellicles with dilute aqueous solutions of luminophores (rhodamine B, carbon dots, polymer dots) and drying under ambient conditions. Simple encapsulation of luminophores renders BC with circularly polarized luminescence with a dissymmetry factor of up to 0.03. The multiple chiral centers of bacterial cellulose provide a primary asymmetric environment that can be further modulated by supramolecular chemistry, which is responsible for its circular polarization ability. We further demonstrate that commercial grade paper may endow luminophores with CPL activity, which reifies the universality of the method.

6

Chen, Jingqi, Yingying Chen, Lijuan Zhao, Lingyan Feng, Feifei Xing, Chuanqi Zhao, Lianzhe Hu, Jinsong Ren, and Xiaogang Qu. "G-quadruplex DNA regulates invertible circularly polarized luminescence." Journal of Materials Chemistry C 7, no. 44 (2019): 13947–52. http://dx.doi.org/10.1039/c9tc04508b.

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Circularly polarized luminescence (CPL) was performed for the first time in G4 research in which chirality transfer from G4 to the achiral dye. Opposite CPL signals are obtained on mirror d-/l-enantiomers and parallel/antiparallel G4 changes.

7

Zheng, Anyi, Tonghan Zhao, Xue Jin, Wangen Miao, and Pengfei Duan. "Circularly polarized luminescent porous crystalline nanomaterials." Nanoscale 14, no. 4 (2022): 1123–35. http://dx.doi.org/10.1039/d1nr07069j.

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An overview of generation, regulation and amplification of circularly polarized luminescence (CPL) in porous crystalline nanomaterials by direct synthesis, chirality induction or adaption, and symmetry breaking pathways.

8

Wang, Chen, Luyao Feng, Junxiao Liu, Jing Fu, Jinglin Shen, and Wei Qi. "Manipulating the Assembly of Au Nanoclusters for Luminescence Enhancement and Circularly Polarized Luminescence." Nanomaterials 12, no. 9 (April 25, 2022): 1453. http://dx.doi.org/10.3390/nano12091453.

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Au nanocluster (AuNCs)-based luminescent functional materials have attracted the interest of researchers owing to their small size, tractable surface modification, phosphorescence lifetime and biocompatibility. However, the poor luminescence quantum yield (QY) of AuNCs limits their practical applications. Herein, we synthesized a type of AuNCs modified by 4,6-diamino-2-mercaptopyrimidine hydrate (DPT-AuNCs). Furthermore, organic acids, i.e., citric acid (CA) and tartaric acid (TA), were chosen for co-assembly with DPT-AuNCs to produce AuNCs-based luminescent materials with enhanced emission. Firstly, it was found that CA could significantly enhance the emission of DPT−AuNCs with the formation of red emission nanofibers (QY = 17.31%), which showed a potential for usage in I− detection. The n···π/π···π interaction between the CA and the DPT ligand was proposed as crucial for the emission. Moreover, chiral TA could not only improve the emission of DPT-AuNCs, but could also transfer its chirality to DPT-AuNCs and induce the formation of circularly polarized luminescence (CPL)-active nanofibers. It was demonstrated that the CPL signal could increase 4.6-fold in a ternary CA/TA/DPT-AuNCs co-assembly system. This work provides a convenient way to build AuNCs-based luminescent materials as probes, and opens a new avenue for building CPL-active materials by achiral NCs through a co-assembly strategy.

9

Wang, Chen, Luyao Feng, Junxiao Liu, Jing Fu, Jinglin Shen, and Wei Qi. "Manipulating the Assembly of Au Nanoclusters for Luminescence Enhancement and Circularly Polarized Luminescence." Nanomaterials 12, no. 9 (April 25, 2022): 1453. http://dx.doi.org/10.3390/nano12091453.

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Au nanocluster (AuNCs)-based luminescent functional materials have attracted the interest of researchers owing to their small size, tractable surface modification, phosphorescence lifetime and biocompatibility. However, the poor luminescence quantum yield (QY) of AuNCs limits their practical applications. Herein, we synthesized a type of AuNCs modified by 4,6-diamino-2-mercaptopyrimidine hydrate (DPT-AuNCs). Furthermore, organic acids, i.e., citric acid (CA) and tartaric acid (TA), were chosen for co-assembly with DPT-AuNCs to produce AuNCs-based luminescent materials with enhanced emission. Firstly, it was found that CA could significantly enhance the emission of DPT−AuNCs with the formation of red emission nanofibers (QY = 17.31%), which showed a potential for usage in I− detection. The n···π/π···π interaction between the CA and the DPT ligand was proposed as crucial for the emission. Moreover, chiral TA could not only improve the emission of DPT-AuNCs, but could also transfer its chirality to DPT-AuNCs and induce the formation of circularly polarized luminescence (CPL)-active nanofibers. It was demonstrated that the CPL signal could increase 4.6-fold in a ternary CA/TA/DPT-AuNCs co-assembly system. This work provides a convenient way to build AuNCs-based luminescent materials as probes, and opens a new avenue for building CPL-active materials by achiral NCs through a co-assembly strategy.

10

He, Dong-Qiang, Hai-Yan Lu, Meng Li, and Chuan-Feng Chen. "Intense blue circularly polarized luminescence from helical aromatic esters." Chemical Communications 53, no. 45 (2017): 6093–96. http://dx.doi.org/10.1039/c7cc01882g.

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Більше джерел

Дисертації з теми "Circularly Polarized Luminescence (CPL)":

1

Li, Tian-Yi, You-Xuan Zheng, and Yong-Hui Zhou. "Iridium(III) phosphorescent complexes with dual stereogenic centers: single crystal, electronic circular dichroism evidence and circularly polarized luminescence properties." Royal Society of Chemistry, 2016. https://tud.qucosa.de/id/qucosa%3A36123.

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Iridium complexes with a chiral metal center and chiral carbons, Λ/Δ-(dfppy)₂Ir(chty-R) and Λ/Δ-(dfppy)2Ir(chty-S), were synthesized and characterized. These isomers have the same steadystate photophysical properties, and obvious offsets in ECD spectra highlight both the chiral sources. Each enantiomeric couple shows mirror-image CPL bands with a dissymmetry factor in the order of 10ˉ³.

2

Mattei, Carlo Andrea. "Élaboration de complexes de coordination d’ions lanthanides combinant les propriétés de molécule aimante et de luminescence circulairement polarisée." Electronic Thesis or Diss., Rennes 1, 2021. https://ged.univ-rennes1.fr/nuxeo/site/esupversions/f7b00a90-2ab1-411e-b9f9-2e2f43b32f59.

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Des ligands binaphtyle dérivés contenant des groupes donneurs P"=" O ont été utilisés pour la synthèse rationnelle de composés de coordination à propriétés multiples avec des unités M〖(hfac)〗_3. L'oxyde chiral de bisphosphine L a agi comme un ligand chélate donnant des espèces racémiques monomères de formule [〖{Ln(hfac)_3 L}〗_3] (Ln= Eu,Dy and Yb). Ces complexes ont été caractérisés structurellement et leurs propriétés physiques ont été étudiées à l'état solide. Le composé [〖{Eu(hfac)_3 L}〗_3] présentait une luminescence centrée sur le métal. Différemment, le ligand L n'a pas sensibilisé l'émission de luminescence pour [〖{Dy(hfac)_3 L}〗_3]. Cependant, ce dernier affichait un comportement SMM induit par l’application d’un champ magnétique. Le complexe [〖{Yb(hfac)_3 L}〗_3] était un exemple de field-induced SMM chiral et luminescent. Pour les espèces à base de Dy(III)- et Yb(III)-, l'aimantation s'est relâchée via un processus Raman similaire sous l'effet d'un champ magnétique externe. Tous ces composés sont sublimés lorsqu'ils sont chauffés à pression réduite. Ensuite, la chimie de coordination des ligands bisphosphates énantiopurs dérivés du binaphtyle (S)/(R)-L^n (n=1,3) and (S,S,S)/(R,R,R)-L^n (n=2,4) a été étudié. La réaction de ces ligands avec des quantités équimolaires des précurseurs métalliques [M(hfac)_3 (H_2 O)_2] (M=Y,Eu,Dy and Yb) a donné des polymères de coordination monodimensionnel et énantiopurs. Avec les ligands (S)/(R)-L^n (n=1,3), deux espèces polymorphes différentes pourraient être cristallisées en changeant les conditions de réaction et la nature de l'ion métallique. composés à base d’ion Dy(III) ont manifesté un comportement field-induced SMM et une émission de luminescence. La corrélation magnéto-optique et les résultats des calculs ab initio sont présentés. Le complexe 〖[Dy(hfac)_3 {(S)-L^1}]〗_n a montré de contributions multiples de la relaxation d'aimantation malgré la présence d'un seul centre cristallographique de Dy(III). La solubilisation des polymères de coordination 〖[M(hfac)_3 {(S)/(R)-L^1}]〗_n a provoqué une réorganisation structurale en espèces monomères de formule [M(hfac)_3 {(S)/(R)-L^1}]. Ceci a été démontré par spectroscopie NMR et calculs DFT. De manière similaire à l'état solide, le complexe [Dy(hfac)_3 {(S)-L^1}] a présenté un comportement field-induced SMM à plusieurs contributions. Les processus régissant la relaxation d'aimantation de 〖[Dy(hfac)_3 {(S,S,S)-L^2}]〗_n et 〖[Dy〖(hfac)〗_3 {(S)-L^3 }]〗_n ont été étudiés plus en détail en appliquant une stratégie de dilution magnétique et d'enrichissement isotopique avec (_ ^163)Dy(III) (I=1⁄2) et (_ ^164)Dy(III) (I=0). Malgré la minimisation des interactions dipolaires et l'absence de spin nucléaire, une forte dépendance de l'aimantation par le champ a toujours été observée. Les ligands (S)/(R)-L^n (n=1,3) et (S,S,S)/(R,R,R)-L^n (n=2,4) ont sensibilisé efficacement le luminescence des espèces à base d'Eu(III). Leur nature énantiopure a favorisé l'émission de CPL à la fois en solution et à l'état solide. Enfin, le comportement SMM induit par le champ et l'émission de CPL ont été observés dans le même composé en utilisant des centres Yb(III). L'utilisation du ligand L^5 à base de TTF et des unités chirales Yb〖{(R)/(S)"-" facam}〗_3 a donné les dimères énantiopurs 〖[Yb〖{(R)/(S)"-" facam}〗_3 (L^5)]〗_2. Le fragment TTF conférait une activité redox. L'application d'un champ statique modéré a révélé une lente relaxation de l'aimantation. L'excitation directe des états ILCT de L^5 a sensibilisé la luminescence centrée sur le métal. De plus, des émissions NIR-CPL en solution et à l'état solide ont été détectées. Le complexe 〖[Yb〖{(R)/(S)"-" facam}〗_3 (L^5)]〗_2 était un SMM redox induit par champ chiral affichant une émission CPL. Avec les complexes à base d' Yb(III) coordonnés par les ligands (S)/(R)-L^n (n=1,3) et (S,S,S)/(R,R,R)-L^n (n=2,4), ce sont les premiers exemples d'émission NIR-CPL à l'état solide documentés pour les complexes moléculaires
Binaphthyl-derived ligands containing P"=" O donor groups were employed for the rational synthesis of multi-properties coordination compounds with M〖(hfac)〗_3 units. The chiral bisphosphine oxide L acted as a chelate ligand giving monomeric racemic species of formula [〖{Ln(hfac)_3 L}〗_3] (Ln= Eu,Dy and Yb). These complexes were structurally characterized and their physical properties were studied in solid state. The compound [〖{Eu(hfac)_3 L}〗_3] exhibited metal-centred luminescence. Conversely, the ligand L was not able to sensitise luminescence emission for [〖{Dy(hfac)_3 L}〗_3]. However, the latter displayed field-induced SMM behaviour. The complex [〖{Yb(hfac)_3 L}〗_3] was an example of a chiral luminescent field-induced SMM. For both Dy(III)- and Yb(III)-based species, the magnetization relaxed via a similar Raman process under the effect of an external magnetic field. All these compounds sublimated when heated at reduced pressure. Subsequently, the coordination chemistry of the enantiopure binaphthyl-derived bisphosphate ligands (S)/(R)-L^n (n=1,3) and (S,S,S)/(R,R,R)-L^n (n=2,4) was studied. Reaction of these ligands with equimolar quantities of the metal precursors [M(hfac)_3 (H_2 O)_2] (M=Y,Eu,Dy and Yb) yielded enantiopure 1D-coordiantion polymers. With ligands (S)/(R)-L^n (n=1,3), two different polymorphic species could be crystallised by changing reaction conditions and nature of the metal ion. The Dy(III)-based compounds manifested field-induced SMM behaviour and luminescence emission. Magneto-optical correlation and results from ab initio calculations are presented. The complex 〖[Dy(hfac)_3 {(S)-L^1}]〗_n showed multiple contributions of the magnetization relaxation despite the presence of a single crystallographic Dy(III) centre. Solubilization of the coordination polymers 〖[M(hfac)_3 {(S)/(R)-L^1}]〗_n caused a structural reorganization to monomeric species of formula [M(hfac)_3 {(S)/(R)-L^1}]. This was demonstrated by NMR spectroscopy and DFT calculations. Similarly to the solid state, complex [Dy(hfac)_3 {(S)-L^1}] exhibited a multi-contribution field-induced SMM behaviour. The processes governing the magnetization relaxation of 〖[Dy(hfac)_3 {(S,S,S)-L^2}]〗_n and 〖[Dy〖(hfac)〗_3 {(S)-L^3 }]〗_n were further investigated by applying a strategy of magnetic dilution and isotopic enrichment with (_ ^163)Dy(III) (I=1⁄2) and (_ ^164)Dy(III) (I=0). Despite the minimisation of the dipolar interactions and the absence of nuclear spin, a strong field dependence of the magnetization was still observed. The ligands (S)/(R)-L^n (n=1,3) and (S,S,S)/(R,R,R)-L^n (n=2,4) efficiently sensitised the luminescence of the Eu(III)-based species. Their enantiopure nature promoted CPL emission in both solution and solid state. Finally, field-induced SMM behaviour and CPL emission were observed in the same compound by employing Yb(III) centres. The use of the functionalized TTF-based ligand L^5 and chiral Yb〖{(R)/(S)"-" facam}〗_3 units gave the enantiopure pair of dimers 〖[Yb〖{(R)/(S)"-" facam}〗_3 (L^5)]〗_2. The TTF fragment conferred redox activity. The application of a moderate static field revealed slow relaxation of the magnetization. Direct excitation of the ILCT states of L^5 sensitised the metal-centred luminescence. Moreover, both solution and solid state NIR-CPL emission were detected. The complex 〖[Yb〖{(R)/(S)"-" facam}〗_3 (L^5)]〗_2 was a redox chiral filed-induced SMM displaying CPL emission. Together with the Yb(III)-based complexes coordinated by the ligands (S)/(R)-L^n (n=1,3) and (S,S,S)/(R,R,R)-L^n (n=2,4), these are the first documented solid state NIR-CPL emissive examples for molecular complexes

3

Pathan, Shaheen. "Développement de matériaux flexibles optiquement actifs basés sur des nanostructures hybrides chirales de modèle d’assemblage moléculaire." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0126.

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Dans ce travail, nous nous sommes concentrés sur la création de nanostructures chirales optiquement actives en fabriquant des nanohélices de silice fluorescente afin d’obtenir des matériaux souple, nanométriques, optiquement actifs pour des applications en tant que matériaux nanophotoniques. Dans cette optique, des nanohélices de silice chirales ont été utilisées pour greffer et organiser des nanocristaux inorganiques fluorescents achiraux tels que des quantums dots, des chromophores, des molécules et des polymères fluorescents selon différentes approches. Ces hélices inorganiques ont été formées par procédé sol-gel en utilisant des auto-assemblages hélicoïdaux organiques de molécules amphiphiles (amphiphile gemini cationique, avec un contre-ion chiral le tartrate) en tant que modèles. Tout d'abord, la surface de la silice hélicoïdale a été fonctionnalisée par l’APTES afin de greffer des quantum dots inorganiques ZnS-AgInS2 possédant divers ligands. Dans la deuxième partie, le polymère de dérivé anthracénique fluorescent a été organisé par dépôt et adsorption à la surface de silice hélicoïdale. Afin d’étudier les propriétés chiroptiques, différentes caractérisations ont été réalisées telle que la spectroscopie du dichroïsme circulaire (CD) et celle de la luminescence circulairement polarisée (CPL).Le premier chapitre présente l’étude bibliographique sur différents systèmes d’auto-assemblage organiques chiraux et leurs propriétés chiroptiques. Les études sur la formation de systèmes auto-assemblés chiraux dans différentes conditions, leur morphologie structurale, les techniques de fabrication et leurs applications sont discutées suivies de l'utilisation de nanocristaux fluorescents, à savoir, les quantums dots (QD) et les polymères fluorescents achiraux sur lesquels les propriétés chiroptiques peuvent être obtenues et leurs applications dans les nanodispositifs optiques, les capteurs et la nano-photonique.Dans la première partie du deuxième chapitre, différentes techniques de caractérisation telles que le microscope électronique en transmission (TEM), le microscope électronique en transmission haute résolution (HRTEM), la microscopie confocale, la spectroscopie UV-Vis, celle de la fluorescence, du dichroïsme circulaire (CD) et de la luminescence circulairement polarisée (CPL) sont décrites. Dans la deuxième partie, la synthèse du gemini 16-2-16 ainsi que son mécanisme d'auto-assemblage, et sa transformation en réplica de silice par l'intermédiaire de la chimie sol-gel sont décrits. Ces nanohélices de silice sont fonctionnalisées par le 3-aminopropyltriéthoxysilane (APTES). Leur analyse est effectuée par analyse thermogravimétrique (TGA) et analyse élémentaire (EA).Dans le troisième chapitre, nous nous sommes concentrés sur la synthèse de QDs inorganiques ((ZnS)x-1(AgInS2)x) avec différentes compositions rapport molaire et leurs caractérisations par TEM, TGA, EA, spectroscopie infrarouge à transformée de Fourier (FTIR), mesures de potentiel zêta, spectroscopie d'absorption et d'émission. Quatre types de ligands ont été utilisés, par échange de ligand, pour recouvrir les QDs : sulfure d'ammonium (AS), acide 3-mercaptopropionique (MPA), l-cystéine (L-Cys) et l'oleylamine (OLA). Ces QDs sont greffés à la surface des hélices de silice modifiée par de l’amine suite à des interactions ioniques. Diverses techniques ont été utilisées pour confirmer leur greffage à la surface des hélices de silice, et les propriétés optiques ont été étudiées par spectroscopie d'absorption et d'émission. Après le greffage, différents résultats ont été observés selon le ligand utilisé : la caractérisation par TEM montre que les QDs sont greffés à la surface des hélices de silice. [...]
In this work, we focused on the creation of optically active chiral nanostructures by fabricating fluorescent silica nanohelices in order to obtain optically active nanoscale soft materials for applications as nanophotonics materials. For this purpose, silica chiral nanohelices were used for grafting and organizing achiral fluorescent inorganic nanocrystals, dyes, molecules, and fluorescent polymers through different approaches. These inorganic helices were formed via sol-gel method using organic helical self–assemblies of surfactant molecules (achiral and cationic gemini surfactant, with chiral counterion, tartrate) as templates. First, the surface of helical silica was functionalized by APTES in order to graft inorganic quantum dots ZnS-AgInS2 with different capping ligands. In the second part, fluorescent anthracene derivative polymer was organized via deposition and absorption on the surface of helical silica. To investigate the chiroptical properties, circular dichroism and circularly polarised luminescence characterization were performed.In the first chapter, the bibliographic study on different chiral organic self-assembling systems and their chiroptical properties are shown. The studies on the formation of chiral self-assembled systems in different conditions, structural morphology, fabrication techniques and their applications are discussed followed by the use of fluorescent nanocrystals, i.e., quantum dots (QDs) and achiral fluorescent polymers on which chiroptical properties can be obtained and their applications in optical nanodevices, sensors, and nano-photonics.In the first part of the second chapter, different characterisation techniques such as transmission electron microscope (TEM) , high resolution transmission electron microscope (HRTEM), and confocal microscopy, UV-Vis spectroscopy and fluorescence spectroscopies, as well as circular dichroism (CD) and circularly polarised luminescence (CPL) spectroscopies are described. In the second part, the synthesis of Gemini 16-2-16 as well as their self-assemblies mechanism, and their transformation to silica replica via sol-gel chemistry are described. These silica nanohelices are functionalized by 3-aminopropyltriethoxysilane (APTES). Their analysis is performed by Thermogravimetric analysis (TGA) and elementary analysis (EA).In the third Chapter, we focused on the synthesis of inorganic ((ZnS)x-1(AgInS2)x) QDs with different compositions molar ratio and its characterizations by TEM, TGA, EA, Fourier-transform infrared spectroscopy (FTIR), zeta potential measurements, absorption, and emission spectroscopy. Four types of ligands were used to cap the QDs via phase ligand exchange as follows: ammonium sulphide (AS), 3-mercaptopropionic acid (MPA), l-cysteine (L-Cys) and the fourth one is oleylamine (OLA). These QDs are grafted on the surface of amine-modified silica helices through ionic interaction. Various techniques were used to show the grafting of QDs on the surface of silica helix, and their optical properties were studied using absorption and emission spectroscopy. After grafting, in each case of ligands, different results were observed as follows: The TEM characterization shows that QDs are grafted on the surface of silica helices. In the case of AS-capped QDs, the helical morphology of silica helices after grafting is destroyed; therefore the further ananlysis was not possible. While, in the cases of QDs with three other ligands MPA, OLA and L-cys, dense and homogeneous grafting of the QDs were observed by TEM and the helical morphology was preserved after their grafting. The HRTEM images were taken on the MPA-QDs@silica helices and energy-dispersive x-ray (EDX) analysis was performed in STEM mode, confirming the QDs elements present on the silica surfaces. [...]

4

Carr, Rachel. "Lanthanide complexes as chiral probes exploiting circularly polarized luminescence." Thesis, Durham University, 2014. http://etheses.dur.ac.uk/10543/.

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A series of studies has been undertaken to facilitate the identification and development of chiral lanthanide complexes that are able to report on changes in their local environment through modulation of the circular polarization of their emission. Reports of such systems remain relatively rare in the literature, notwithstanding the prevalence and importance of chirality in biological systems. The work described herein is separated into five chapters, the first of which comprises a discussion of relevant background information, along with a comprehensive review of responsive lanthanide-based CPL probes reported to date. A classification of these probes is built up, which informs the content of the following three chapters. Chapter 2 describes work undertaken in the pursuit of a novel lanthanide-based system for use as a CPL probe for the detection of proteins. The synthesis of an enantiopure lanthanide complex was undertaken and characterisation of this system carried out with reference to a structurally related racemic complex. A series of comparative investigations designed to probe the relative protein binding capability of these complexes was subsequently performed, which revealed that the observation of induced CPL from racemic lanthanide systems may be brought about by a change in complex constitution. This is the first example of such an effect from a well-defined racemic lanthanide complex in solution. Chapter 3 goes on to detail studies undertaken to demonstrate the utility of this racemic lanthanide system as a probe for chiral detection. Chapter 4 describes investigations carried out in an attempt to identify new systems exhibiting chiral quenching effects in solution. Initially, two pairs of enantiomeric electron-rich quenching species were assessed for their ability to quench the emission from an enantiopure DOTA-derived lanthanide complex differentially. Subsequently, investigations were focussed on examining the quenching of emission from novel enantiopure lanthanide complexes based on a 1,4,7-triazacyclononane framework, using cobalt complexes as the quenching species. Finally, Chapter 5 contains experimental procedures for each compound synthesised, as well as general experimental procedures.

5

San, Jose Benedict Arcena. "Polarized Luminescence and Chiroptical Switching Functionalities of Liquid Crystalline and Chiral Conjugated Polymers." Master's thesis, 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188612.

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6

Kubo, Hiromu. "Design and Synthesis of Helicene Derivatives with Excellent Chiroptical Properties." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263690.

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7

Scalabre, Antoine. "induction de chiralité supramoléculaire : vers de nouveaux nano-objets chiro-optiques hybrides." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0157/document.

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La polarisation de la lumière, bien que connue depuis fort longtemps, pourrait être plus exploitée. Cependant, de plus en plus d’entreprises de pointe dans les domaines de la sécurité et la transmission d’information commencent à l’utiliser. Une raison de la sous-exploitation actuelle de la polarisation vient des méthodes de polarisation, qui ont une transmission de la lumière limitée (généralement jusqu’à 45%). Afin d’outrepasser cette limite physique, un moyen est d’utiliser des matériaux fluorescents émettant une lumière polarisée. Cependant, la synthèse et la purification de tels matériaux sont compliquées et obtenir les deux énantiomères n’est pas toujours possible. Ce travail se concentre sur une nouvelle méthode de synthèse, plus simple, utilisant des nano-structures hybrides ou inorganiques hélicoïdale, et des luminophores organiques pouvant interagir ensemble. L’agrégation chirale des chromophores autour des structures formera ainsi des nano-objets fluorescents chiraux. Le premier chapitre explique comment la chiralité est aujourd’hui présente dans tous les domaines et à toutes les échelles, des molécules aux objets du quotidien. Nous y étudierons également l’induction de la chiralité à différentes échelles. Le second aspect de ce travail, l’interaction lumière-matière, sera également mis en avant, aussi bien concernant l’absorption que l’émission lumineuse, mais aussi en quoi l’assemblage des molécules peut affecter ces propriétés. Nous nous pencherons également sur les cas très particuliers du dichroïsme circulaire et de la luminescence circulairement polarisée. Pour finir, nous verrons quels sont les matériaux actuels existant pour obtenir ces propriétés et quels sont leurs inconvénients. Afin d’outrepasser ces défauts, nous avons choisi d’utiliser deux systèmes. Le premier, constitué de nano-hélices organiques dans une coque de silice a pour avantage d’utiliser à la fois une induction de chiralité par assemblage des chromophores organiques, mais aussi une seconde induction de la chiralité à l’échelle moléculaire. L’inconvénient étant que ce système n’est pas très robuste à un changement d’environnement. Pour résoudre cet inconvénient, nous n’avons conservé, dans un second temps, que la coque de silice afin de l’utiliser comme patron pour supporter le greffage covalent de luminophores à sa surface. Dans le second chapitre, la méthode de synthèse des nano-structures sera présentée. De même le choix des différents luminophores utilisés dans ces travaux sera justifié, et leur voie de synthèse, expliquée. Enfin, les différentes méthodes de caractérisation seront détaillées. Le troisième chapitre portera sur les résultats obtenus lors de l’intégration de chromophores non-chiraux dans les hélices hybrides, ou leur de greffage sur les structures inorganiques. Nous y verrons l’importance à la fois de l’assemblage intermoléculaire, mais aussi de l’interaction avec un environnement chiral, pour l’induction de chiralité dans le but d’obtenir dichroïsme circulaire et luminescence circulairement polarisée. Les différents chromophores utilisés y sont présentés et comparés permettant la mise en évidence des principaux facteurs aidant à l’induction de chiralité pour chaque type de structure. Enfin, un dernier chapitre s’intéressera à des systèmes plus complexes utilisant des molécules présentant en solution des propriétés chiro-optiques, ou ayant la capacité de s’agréger en nano-structures ayant de telles propriétés, et ce afin de savoir si leurs propriétés sont ajustables grâce à l’utilisation des hélices hybrides pour leur imposer une agrégation spécifique. Une dernière approche a également été étudiée, en synthétisant des quantum-dots carbonés fluorescents à partir des nano-structures hybrides. Ces quantum-dots, s’ils conservent la forme de la structure initiale, pourraient posséder un dichroïsme circulaire et une luminescence circulairement polarisée sans besoin de les complexer avec une molécule chirale
The polarization of light, despite being known since long time, is recently at the center of renewed interest. More and more high technology companies in the fields of safety and information transmission are starting to exploit this property. One bottleneck for their use comes from the limitation in the light transmission of current methods of polarization (typically up to 45%). In order to overpass this physical limitation, one possible approach would be to use fluorescent materials emitting polarized light. However, the synthesis and purification of such materials is complex and obtaining both enantiomers is not always possible. The current work focus on a new synthetic pathway, possibly simpler and more versatile, using chiral hybrid or inorganic nano-helices and organic fluorophores interacting together. The aggregation of chromophores around the template will form chiral fluorescent nano-objects. The first chapter explains how chirality is present in many fields and at every scale, from molecules to daily objects. We will discuss the way of inducting or transferring chirality. The second facet of this work, light-matter interactions, will also be explained, concerning both absorption and emission of light, but also on how molecular assembly can affect these properties. We will study into detail the very particular case of circular dichroism and circularly polarized luminescence. Finally, we will see the existing systems that are used to obtain these properties and the drawback of these materials. In this work, we chose to use two systems. The first, constituted of organic nano-helices in a silica shell, has the advantage of using the organic template confined in chiral nano-space to induce chirality to the organic chromophores in interaction with them molecularly, but also through aggregation due to the confinement. The disadvantage being that this system is not robust toward environmental changes. The alternative approach is to use the silica shell as an inorganic template for the covalent grafting of fluorophores onto its surface. In the second chapter, the method for the synthesis of nano-structures is described, along with an explanation on the choice and synthesis of the chromophores used in this study. Finally, the characterization processes used are detailed. The third chapter will focus on the results we obtained when integrating achiral chromophores into hybrid helices or by grafting then onto the silica surface. We will see the importance of the intermolecular assembly and of the interaction with a chiral environment to obtain circular dichroism and circularly polarized luminescence through chiral induction. Various fluorophores are presented and compared allowing the understanding of the key parameters for chirality induction of each type of structure.In the last chapter, more complex systems are studied using molecules presenting chiroptical properties in solution state or having the ability to form self-assemblies showing such properties. The objective will be to tune the chiroptical properties of these chromophores, by the use of hybrid helices to force a specific organization. The last part will focus on the synthesis of fluorescent carbon based quantum dots using hybrid structures. These quantum dots, can retain the shape of the original structure and show circular dichroism or circularly polarized luminescence without needing to form a complex with an external source of molecular chirality

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Gauthier, Étienne. "Chiral complexes based on helicenic N-heterocyclic carbenes : synthesis, structure, photophysical and chiroptical properties." Thesis, Rennes 1, 2020. http://www.theses.fr/2020REN1S083.

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Dans le cadre de ma thèse, de nouveaux complexes de métaux de transitions (rhénium, iridium, cuivre, or) chiraux possédant des ligands NHC-hélicéniques ont été synthétisés et les propriétés chiroptiques et photophysiques ont été étudiées. Le premier sujet d’étude s’est focalisé sur l’étude de complexes de rhénium(I) cyclométallés par des ligands hélicéniques-NHC de type (N^C:) émettant de la phosphorescence circulairement polarisée. Une influence du design du ligand, des ligands ancillaires et de la géométrie des complexes sur les propriétés chiroptiques et photophysiques a été observée. Le deuxième projet a été consacré à l’étude de nouveaux complexes chiraux d’iridium cyclométallés possédant un ou plusieurs ligands N-[6]helicenyl-benzimidazolylidène. L’attention s’est ensuite portée sur des complexes possédant des ligands monodentes. Ainsi, dans le cadre d’un troisième projet, un complexe de cuivre portant un ligand NHC-hélicénique démontrant des propriétés de fluorescence circulairement polarisée a pu être obtenu avec succès. Enfin, des complexes chiraux d’or coordinés par des ligands hélicéniques-NHC ont été préparés. Pendant ce projet, les propriétés électroniques (sigma-donatrice et pi-acceptrice) d’un carbène hélicénique ont été quantifiées
My PhD work was dedicated to the synthesis and the study of novel chiral transition metal complexes (rhenium, iridium, copper, gold) bearing NHC-helicenes ligands and to the study of their chiroptical and photophysical properties. The first subject focused on the preparation and the study of CP-phosphorescent complexes of cyclometalated rhenium(I) complexes bearing NHC-helicenic (N^C:) ligands. The influence of the ligand design, ancillary ligands and geometry of the complexes on the chiroptical and photophysical properties has been highlighted. In the second project, we have prepared novel chiral cyclometalated iridium complexes bearing one or multiple N-[6]helicenyl- benzimidazolylidene ligands.Then, the attention has been focused on monodentate complexes. Thus, in the third project, a chiral copper complex bearing a helicenic-NHC ligand which emits circularly polarized fluorescence was successfully obtained. Finally, chiral monodentate helicenic-NHC gold(I) complexes have been prepared. During this project, the electronic properties (sigma-donating et pi-accepting) of a helicenic-NHC were investigated

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Nishikawa, Tsuyoshi. "Screw-sense Control of Helical Poly(quinoxaline-2,3-diyl)s for Chirality-switchable Asymmetric Catalysts and Luminescent Materials." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225637.

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Schulte, Thorben Rüdiger. "Metal- and Ligand-Centered Chirality in Square-Planar Coordination Compounds." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://hdl.handle.net/21.11130/00-1735-0000-0005-126A-0.

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Книги з теми "Circularly Polarized Luminescence (CPL)":

1

Mori, Tadashi, ed. Circularly Polarized Luminescence of Isolated Small Organic Molecules. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-2309-0.

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2

Mori, Tadashi. Circularly Polarized Luminescence of Isolated Small Organic Molecules. Springer, 2020.

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3

Mori, Tadashi. Circularly Polarized Luminescence of Isolated Small Organic Molecules. Springer Singapore Pte. Limited, 2021.

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4

Wu, Tao, You-Xuan Zheng, Giovanna Longhi, and Ga-Lai Law, eds. Chiral Organic Chromophoric Systems in the Enhancement of Circularly Polarized Luminescence. Frontiers Media SA, 2021. http://dx.doi.org/10.3389/978-2-88966-708-6.

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Частини книг з теми "Circularly Polarized Luminescence (CPL)":

1

Gussakovsky, Eugene. "Circularly Polarized Luminescence (CPL) of Proteins and Protein Complexes." In Reviews in Fluorescence 2008, 425–59. New York, NY: Springer New York, 2009. http://dx.doi.org/10.1007/978-1-4419-1260-2_18.

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2

Morisaki, Yasuhiro. "Circularly Polarized Luminescence (CPL) Based on Planar Chiral [2.2]Paracyclophane." In Progress in the Science of Functional Dyes, 343–74. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4392-4_10.

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3

Chen, Chuan-Feng, and Yun Shen. "Circularly Polarized Luminescence and Organic Electronics." In Helicene Chemistry, 229–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-53168-6_12.

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4

Zinna, Francesco, Elodie Brun, Alexandre Homberg, and Jérôme Lacour. "Circularly Polarized Luminescence from Intramolecular Excimers." In Circularly Polarized Luminescence of Isolated Small Organic Molecules, 273–92. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-2309-0_12.

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5

Nakashima, Takuya, and Tsuyoshi Kawai. "Photo-Switching of Circularly Polarized Luminescence." In Circularly Polarized Luminescence of Isolated Small Organic Molecules, 177–95. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-2309-0_8.

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6

Hall, Michael John, and Santiago de la Moya. "BODIPY Based Emitters of Circularly Polarized Luminescence." In Circularly Polarized Luminescence of Isolated Small Organic Molecules, 117–49. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-2309-0_6.

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7

Imai, Yoshitane. "Circularly Polarized Luminescence from Solid-State Chiral Luminophores." In Advances in Organic Crystal Chemistry, 325–40. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-5085-0_16.

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8

Suzuki, Satoko. "Principles and Applications of Circularly Polarized Luminescence Spectrophotometer." In Circularly Polarized Luminescence of Isolated Small Organic Molecules, 309–25. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-2309-0_14.

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9

Imai, Yoshitane. "Circularly Polarized Luminescence of Axially Chiral Binaphthyl Fluorophores." In Circularly Polarized Luminescence of Isolated Small Organic Molecules, 11–30. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-2309-0_2.

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10

Crassous, Jeanne. "Circularly Polarized Luminescence in Helicene and Helicenoid Derivatives." In Circularly Polarized Luminescence of Isolated Small Organic Molecules, 53–97. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-2309-0_4.

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Тези доповідей конференцій з теми "Circularly Polarized Luminescence (CPL)":

1

Barnes, Michael D., Ruthanne Hassey-Paradise, and D. Venkataraman. "Circularly Polarized Luminescence from Single Chiral Molecules." In Laser Science. Washington, D.C.: OSA, 2009. http://dx.doi.org/10.1364/ls.2009.lsmb4.

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2

Szeto, Bryan, Peter C. P. Hrudey, Mike Taschuk, and Michael J. Brett. "Circularly polarized luminescence from chiral thin films." In Integrated Optoelectronic Devices 2006, edited by Liang-Chy Chien. SPIE, 2006. http://dx.doi.org/10.1117/12.646452.

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3

Bjorknas, Kristina, Peter Raynes, Sandra Gilmour, Victor Christou, and Kai Look. "Circularly polarized luminescence from an organoterbium emitter embedded in a chiral polymer." In International Symposium on Optical Science and Technology, edited by Akhlesh Lakhtakia, Graeme Dewar, and Martin W. McCall. SPIE, 2002. http://dx.doi.org/10.1117/12.472990.

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4

Le, Khai Q., and Hiromi Okamoto. "Dissymmetry between left- and right-handed circularly polarized photoluminescence enhancement of plasmonic nanostructures." In JSAP-OSA Joint Symposia. Washington, D.C.: Optica Publishing Group, 2017. http://dx.doi.org/10.1364/jsap.2017.5a_a410_2.

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We report here strong dissymmetry between left- and right-handed circularly polarized photoluminescence enhancement (PLE) induced by two-dimensional chiral gold nanostructures, which can be utilized to provide circularly polarized luminescence. We employed the dye molecule IR-125 as an emitter whose photoluminescence was enhanced by a near-field interaction between the chiral plasmon and the molecule. The difference between the PLE factors for left- and right-handed circular polarizations induced by the near-field enhancement was correlated to the dissymmetry of left- and right-handed extinction of the gold nanostructures.

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Yamamoto, Yohei, Osamu Oki, HIroshi Yamagishi та Takashige Omatsu. "Robust angular anisotropy of circularly polarized luminescence from chiral π-conjugated polymer microspheres with twisted bipolar configuration". У Optical Manipulation and Structured Materials Conference, редактор Takashige Omatsu. SPIE, 2022. http://dx.doi.org/10.1117/12.2658794.

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6

Akimoto, R., K. Ando, F. Sasaki, S. Kobayashi, and T. Tani. "Femtosecond Carrier Spin Dynamics in CdTe/Cd0.6Mn0.4Te Quantum Wells." In International Conference on Ultrafast Phenomena. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/up.1996.tue.38.

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In recent years, many interests are focused on the spin relaxation in the semiconductor hetero structures such as the quantum wells, since the spin relaxation time is much faster than the carrier life time. In the quantum wells, the degeneracy between the heavy hole and the light hole excitons is lifted, so that the one spin state in the conduction- and valence-band state can be excited selectively by the circularly polarized light. In the previous study of the spin relaxation in the quantum wells, the pump-probe using the circular polarization where the wavelength of the pump and the prove are the same and resonant with the heavy hole exciton[1-4], or the time-resolved luminescence measurement where the heavy hole exciton is excited resonantly by the circularly polarized pulse, and the decay of the circular polarization in the luminescence is measured[5-9], have been employed. In both cases of the measurements for the undoped quantum wells, the spin relaxation of the heavy hole exciton is contributed to both the electron spin relaxation and the heavy hole spin relaxation, simultaneously. A possible way to isolate the electron spin relaxation from the heavy hole relaxation in GaAs/AlGaAs quantum wells, is to use the p-doped quantum wells for the electron spin relaxation and the n-doped one for the heavy hole spin relaxation[9]. However, the doped quantum wells may be quite different from undoped quantum wells in the spin relaxation mechanism such as carrier-impurity scattering, the Coulomb screening of the carriers and so on. Therefore, here, we present an approach to measure the electron spin relaxation separately from the heavy hole one in the undoped quantum wells by the measurement of the femtosecond time-resolved circular dichroic spectrum. The present pump-probe method has the unconventional configuration in the absorption saturation measured from unoccupied light hole (lh) spin state and occupied heavy hole (hh) spin state simultaneously using the circularly polarized probe pulse with the continuum spectrum. The sample used in our experiments is CdTe/Cd0.6Mn0.4Te quantum wells, where the sp-d exchange interaction between the carrier spin in the well and the Mn ion spin in the barrier can be controlled by the confinement degree of the carrier wave function and we can examine the effect of the sp-d exchange interaction on the carrier spin relaxation.