Umfassende Photophysikalische Charakterisierung Fortschrittlicher Hexa-peri-hexabenzocoronen und Kohlenstoff-Nanopartikel Systeme

To minimize the consequences and damages of the impending climate change, we must face great challenges in the generation and consumption of green energy. The corona pandemic serves as a warning for the plurality of problems, which we have to fear in the course of the climate change. The discovery and design of new functional materials, comprised of versatile molecular building blocks, is necessary to realize the transformation to new technologies like battery powered vehicles or flexible and cheap photovoltaic systems. In this thesis, the focus is set on carbon-based materials. Carbon is a highly versatile element, which can undergo multiple binding motifs to form various materials with intriguing physical properties. The aim of this thesis is to substantially contribute to the comprehensive photophysical understanding of two promising carbon materials, hexa-peri-hexabenzocoronene and carbon nanodot, with the focus on the elucidation of the ground and excited state properties, which is investigated by means of steady-state and time-resolved spectroscopies. In the first chapter, photophysical investigations of hexa-peri-hexabenzocoronene containing systems are presented. First, the thesis reports about investigations on the basic ground and excited state properties of pristine and single-substituted hexa-peri-hexabenzocoronenes. The optoelectronic impact of electron-withdrawing groups is investigated, showing that the electronic system is increasingly perturbed until the formation of charge transfer interactions. Next, a structural modification is realized by the introduction of helicity in a hexa-peri-hexabenzocoronene dimer. The extension of the delocalized pi-system and the symmetry-reduction leads to redshifted and modified absorption features and drastically enhanced fluorescence. Functionalization with electron-withdrawing groups individually fine-tune the ground and excited state properties up to the evolution of charge or electron transfer events. Third, hexa-peri-hexabenzocoronene is integrated in an electron donor-acceptor system with perylene/naphthalene diimides. In the synthesis, two conformers evolve, which differ spatially by a helical or linear alignment. Depending on this, the conformers exhibit different properties, for example in terms of aggregation, which impacts the charge and electron transfer interactions. Fourth, hexa-peri-hexabenzocoronene is decorated with multiple porphyrins in different geometrical arrangements to investigate the mediation of interporphyrin communication through the delocalized system of hexa-peri-hexabenzocoronene. The biporphyrinic cavities created in the bis-ortho- and hexa-substituted conjugate possess a high affinity to complex fullerenes C60 and C70. Ground and excited state experiments, regarding the intermolecular interactions and electron transfer, are performed. Fifth, hexa-peri-hexabenzocoronene is functionalized with a porphyrin and a fullerene unit in ortho-, meta-, and para-positions. Electron transfer interactions, mediated through the hexa-peri-hexabenzocoronene, are examined with respect to the different regioisomeric orientations. The excited state dynamics are compared to the corresponding hexaphenylbenzene derivatives, which exhibit a declined conjugation and an increased flexibility. In the second chapter, the focus is on carbon nanodots regarding their electron donor/acceptor properties and the composition. First, the electron accepting properties are investigated in covalently linked conjugates, consisting of carbon nanodots and extended tetrathiafulvalenes. Electron transfer in the excited state is observed on a picosecond timescale. Second, supramolecular complexes of carbon nanodots and porphyrins are the center of attention. Non-covalent interactions are realized by hydrogen bonding interactions between the carboxylic groups of the carbon nanodots and amidine groups of the porphyrins, which are attached at the meso-position. Charge transfer events are studied in anhydrous conditions. Third, the interplay in covalent conjugates of nitrogen-doped carbon nanodots and perylene and/or naphthalene diimides is elucidated. Naphthalene diimides lack interactions with carbon nanodots, while perylene diimides undergo ground and excited state interactions, visible by fluorescence quenching and the emergence of electron transfer in the excited state. Fourth, the formation and nature of versatile photoactive species, which are formed during the synthesis, within the carbon nanodot solution is investigated. For this, the solution is separated into several fractions by column chromatography. Trends in the fluorescent nature and the composition of the single fractions are elucidated by time-resolved fluorescence spectroscopy

Special issue editorial: Key results of the european human biomonitoring initiative - HBM4EU

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Photon- and Charge-Management in Advanced Energy Materials: Combining 0D, 1D, and 2D Nanocarbons as well as Bulk Semiconductors with Organic Chromophores

In this contribution, seminal works in the area of photon- and charge-management are highlighted with focus on covalent electron donor-acceptor conjugates built around porphyrins (Ps), on one hand, and 0D, 1D, and 2D nanocarbons, on the other hand. Photons in these conjugates are managed by Ps, while 0D, 1D, and 2D nanocarbons serve as the active component, which enable managing charges. With a few leading examples, it can be explored much beyond the simple photon- and charge-management characterization and emphasize photovoltaics and photocatalysis to convert and store energy. This contribution concludes by highlighting recent progress in mixing and matching the unique charge-management features of nanocarbons in the design of multidimensional nanocarbons.Fil: Cadranel, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Física; Argentina. Universitat Erlangen-Nuremberg; AlemaniaFil: Haines, Philipp. Universitat Erlangen-Nuremberg; AlemaniaFil: Kaur, Ramandeep. Universitat Erlangen-Nuremberg; AlemaniaFil: Menon, Arjun. Universitat Erlangen-Nuremberg; AlemaniaFil: Münich, Peter W.. Universitat Erlangen-Nuremberg; AlemaniaFil: Schol, Peter R.. Universitat Erlangen-Nuremberg; AlemaniaFil: Guldi, Dirk. Universitat Erlangen-Nuremberg; Alemani

A Functional Hexaphenylbenzene Library Comprising of One, Three, and Six Peripheral Rylene‐Diimide Substituents

Abstract Synthesis and characterization of a series of rylene‐diimide substituted hexaphenylbenzenes (HPBs) is presented. The direct connection of the rylene‐diimide units to the HPBs via the imide‐N‐position without any linkers as well as the use of naphthalene‐diimides (NDIs) next to perylene‐diimides (PDIs) is unprecedented. While mono‐substituted products were obtained by imidization reactions with amino‐HPB and the respective rylene‐monoimides, key step for the formation of tri‐ and hexa‐substituted HPBs is the Co‐catalysed cyclotrimerization. Particular emphasis for physic‐chemical characterization was on to the number of NDIs/PDIs per HPB and the overall substitution patterns. Lastly, Scholl oxidation conditions were applied to all HPB systems to generate the corresponding hexa‐peri‐hexabenzocoronenes (HBCs). Importantly, the efficiency of the transformation strongly depends on the number of NDIs/PDIs. While three rylene‐diimide units already hinder the Scholl reaction, the successful synthesis of mono‐substituted HBCs is possible

Exploring Tetrathiafulvalene-Carbon Nanodots Conjugates in Charge Transfer Reactions

Carbon nanodots (CNDs) have been synthesized using low-cost and biocompatible starting materials such as citric acid/urea, under microwave irradiation and constant pressure conditions. The obtained pressure synthesized CNDs (pCND) were covalently modified with photo- and electro-active π-extended tetrathiafulvalene (exTTF) by means of a two-step esterification reaction affording pCND-exTTF. The electronic interactions between the CNDs and exTTF were investigated in the ground and excited states. Ultrafast pump-probe experiments assisted in corroborating that charge separation governs the deactivation of photoexcited pCND-exTTF. These size-regular structures, as revealed by AFM, are stable electron donor-acceptor conjugates of interest for a better understanding of basic processes such as artificial photosynthesis, catalysis and photovoltaics, involving readily available fluorescent nanodots

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Multidifferential study of identified charged hadron distributions in ZZ-tagged jets in proton-proton collisions at s=\sqrt{s}=13 TeV

Jet fragmentation functions are measured for the first time in proton-proton collisions for charged pions, kaons, and protons within jets recoiling against a $Z$ boson. The charged-hadron distributions are studied longitudinally and transversely to the jet direction for jets with transverse momentum 20 $< p_{\textrm{T}} < 100$ GeV and in the pseudorapidity range $2.5 < \eta < 4$. The data sample was collected with the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.64 fb$^{-1}$. Triple differential distributions as a function of the hadron longitudinal momentum fraction, hadron transverse momentum, and jet transverse momentum are also measured for the first time. This helps constrain transverse-momentum-dependent fragmentation functions. Differences in the shapes and magnitudes of the measured distributions for the different hadron species provide insights into the hadronization process for jets predominantly initiated by light quarks.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-013.html (LHCb public pages

Study of the B−→Λc+Λˉc−K−B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-} decay

The decay $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ is studied in proton-proton collisions at a center-of-mass energy of $\sqrt{s}=13$ TeV using data corresponding to an integrated luminosity of 5 $\mathrm{fb}^{-1}$ collected by the LHCb experiment. In the $\Lambda_{c}^+ K^{-}$ system, the $\Xi_{c}(2930)^{0}$ state observed at the BaBar and Belle experiments is resolved into two narrower states, $\Xi_{c}(2923)^{0}$ and $\Xi_{c}(2939)^{0}$, whose masses and widths are measured to be $$m(\Xi_{c}(2923)^{0}) = 2924.5 \pm 0.4 \pm 1.1 \,\mathrm{MeV}, \\ m(\Xi_{c}(2939)^{0}) = 2938.5 \pm 0.9 \pm 2.3 \,\mathrm{MeV}, \\ \Gamma(\Xi_{c}(2923)^{0}) = \phantom{000}4.8 \pm 0.9 \pm 1.5 \,\mathrm{MeV},\\ \Gamma(\Xi_{c}(2939)^{0}) = \phantom{00}11.0 \pm 1.9 \pm 7.5 \,\mathrm{MeV},$$ where the first uncertainties are statistical and the second systematic. The results are consistent with a previous LHCb measurement using a prompt $\Lambda_{c}^{+} K^{-}$ sample. Evidence of a new $\Xi_{c}(2880)^{0}$ state is found with a local significance of $3.8\,\sigma$, whose mass and width are measured to be $2881.8 \pm 3.1 \pm 8.5\,\mathrm{MeV}$ and $12.4 \pm 5.3 \pm 5.8 \,\mathrm{MeV}$, respectively. In addition, evidence of a new decay mode $\Xi_{c}(2790)^{0} \to \Lambda_{c}^{+} K^{-}$ is found with a significance of $3.7\,\sigma$. The relative branching fraction of $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ with respect to the $B^{-} \to D^{+} D^{-} K^{-}$ decay is measured to be $2.36 \pm 0.11 \pm 0.22 \pm 0.25$, where the first uncertainty is statistical, the second systematic and the third originates from the branching fractions of charm hadron decays.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-028.html (LHCb public pages

Physics case for an LHCb Upgrade II - Opportunities in flavour physics, and beyond, in the HL-LHC era

The LHCb Upgrade II will fully exploit the flavour-physics opportunities of the HL-LHC, and study additional physics topics that take advantage of the forward acceptance of the LHCb spectrometer. The LHCb Upgrade I will begin operation in 2020. Consolidation will occur, and modest enhancements of the Upgrade I detector will be installed, in Long Shutdown 3 of the LHC (2025) and these are discussed here. The main Upgrade II detector will be installed in long shutdown 4 of the LHC (2030) and will build on the strengths of the current LHCb experiment and the Upgrade I. It will operate at a luminosity up to 2×1034 cm−2s−1, ten times that of the Upgrade I detector. New detector components will improve the intrinsic performance of the experiment in certain key areas. An Expression Of Interest proposing Upgrade II was submitted in February 2017. The physics case for the Upgrade II is presented here in more depth. CP-violating phases will be measured with precisions unattainable at any other envisaged facility. The experiment will probe b → sl+l−and b → dl+l− transitions in both muon and electron decays in modes not accessible at Upgrade I. Minimal flavour violation will be tested with a precision measurement of the ratio of B(B0 → μ+μ−)/B(Bs → μ+μ−). Probing charm CP violation at the 10−5 level may result in its long sought discovery. Major advances in hadron spectroscopy will be possible, which will be powerful probes of low energy QCD. Upgrade II potentially will have the highest sensitivity of all the LHC experiments on the Higgs to charm-quark couplings. Generically, the new physics mass scale probed, for fixed couplings, will almost double compared with the pre-HL-LHC era; this extended reach for flavour physics is similar to that which would be achieved by the HE-LHC proposal for the energy frontier

LHCb upgrade software and computing : technical design report

This document reports the Research and Development activities that are carried out in the software and computing domains in view of the upgrade of the LHCb experiment. The implementation of a full software trigger implies major changes in the core software framework, in the event data model, and in the reconstruction algorithms. The increase of the data volumes for both real and simulated datasets requires a corresponding scaling of the distributed computing infrastructure. An implementation plan in both domains is presented, together with a risk assessment analysis