Search

Your search keyword '"Fischer, Tillmann G."' showing total 11 results
Start Over Author "Fischer, Tillmann G."
11 results on '"Fischer, Tillmann G."'

1. Impact of Chlorine on the Internal Transition Rates and Excited States of the Thermally Delayed Activated Fluorescence Molecule 3CzClIPN

Author

Streiter, Martin, Fischer, Tillmann G., Wiebeler, Christian, Reichert, Sebastian, Langenickel, Jörn, Zeitler, Kirsten, and Deibel, Carsten

Subjects
Physics - Chemical Physics
Abstract

We analyze internal transition rates and the singlet-triplet energy gap of the thermally activated delayed fluorescence (TADF) molecule 3CzClIPN, which recently was introduced as an efficient photocatalyst. Distribution and origin of the non-monoexponential decays, which are commonly observed in TADF films, are revealed by analysis of transient fluorescence with an inverse Laplace transform. A numerically robust global rate fit routine, which extracts all relevant TADF parameters by modeling the complete set of data, is introduced. To compare and verify the results, all methods are also applied to the well-known 4CzIPN. The influence of the molecular matrix is discussed by embedding low concentrations of TADF molecules in polystyrene films. Finally, quantum chemical calculations are compared to the experimental results to demonstrate that the chlorine atom increases the charge transfer character of the relevant states, resulting in a reduction of the singlet-triplet energy gap.

Published
2020
Full Text
View/download PDF

3. Enhancing FAIRdata by providing digital workflows from data generation to the publication of data: an open source approach described for cyclic voltammetry

Author

Herrmann, David, primary, Hodapp, Patrick, additional, Starman, Martin, additional, Huang, Pei-Chi, additional, Lin, Chia-Lin, additional, Le, Lan, additional, Klar, Jochen, additional, Bizzarri, Claudia, additional, Roese, Philipp, additional, Oppel, Niklas, additional, Fischer, Tillmann G., additional, Tremouilhac, Pierre, additional, Holzhauer, Laura, additional, Herres-pawlis, Sonja, additional, Hoffmann, Alexander, additional, Seitz, Tobias, additional, Zeitler, Kirsten, additional, Dorn, Alrik, additional, Jung, Nicole, additional, and Bräse, Stefan, additional

Published
2023
Full Text
View/download PDF

5. Data format standards in analytical chemistry

Author

Rauh, David, primary, Blankenburg, Claudia, additional, Fischer, Tillmann G., additional, Jung, Nicole, additional, Kuhn, Stefan, additional, Schatzschneider, Ulrich, additional, Schulze, Tobias, additional, and Neumann, Steffen, additional

Published
2022
Full Text
View/download PDF

6. Harmonising, Harvesting, and Searching Metadata across a Repository Federation.

Author

Neumann, Steffen, Bach, Felix, Castro, Leyla, Fischer, Tillmann G., Hofmann, Stefan, Pei-Chi Huang, Jung, Nicole, Katabathuni, Bhavin, Mauz, Fabian, Meier, Rene, Nainala, Venkata Chandrasekhar, Rayya, Noura, Steinbeck, Christoph, and Koepler, Oliver

Abstract

The collection of metadata for research data is an important aspect in the FAIR principles. The schema.org and Bioschemas initiatives created a vocabulary to embed markup for many different types, including BioChemEntity, ChemicalSubstance, Gene, MolecularEntity, Protein, and others relevant in the Natural and Life Sciences with immediate benefits for findability of data packages. To bridge the gap between the worlds of semanticweb-driven JSON+LD metadata on the one hand, and established but separately developed interface services in libraries, we have designed an architecture for harmonising, federating and harvesting metadata from several resources. Our approach is to serve JSON+LD embedded in an XML container through a central OAI-Provider. Several resources in NFDI4Chem provide such domain-specific metadata. The CKAN-based NFDI4Chem search service can harvest this metadata using an OAI-PMH harvester extension that can extract the XML-encapsulated JSON+LD metadata, and has search capabilities relevant in the chemistry domain. We invite the community to collaborate and reach a critical mass of providers and consumers in the NFDI. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

7. Versatile Visible-Light-Driven Synthesis of Asymmetrical Phosphines and Phosphonium Salts

Author

Arockiam, Percia-Beatrice, Lennert, Ulrich, Graf, Christina, Rothfelder, Robin, Scott, Daniel J., Fischer, Tillmann G., Zeitler, Kirsten, and Wolf, Robert

Subjects
alkylation, arylation, phosphane, phosphorus, photocatalysis, 540 Chemie, ddc:540
Abstract

Asymmetrically substituted tertiary phosphines and quaternary phosphonium salts are used extensively in applications throughout industry and academia. Despite their significance, classical methods to synthesize such compounds often demand either harsh reaction conditions, prefunctionalization of starting materials, highly sensitive organometallic reagents, or expensive transition-metal catalysts. Mild, practical methods thus remain elusive, despite being of great current interest. Herein, we describe a visible-light-driven method to form these products from secondary and primary phosphines. Using an inexpensive organic photocatalyst and blue-light irradiation, arylphosphines can be both alkylated and arylated using commercially available organohalides. In addition, the same organocatalyst can be used to transform white phosphorus (P-4) directly into symmetrical aryl phosphines and phosphonium salts in a single reaction step, which has previously only been possible using precious metal catalysis.

Published
2020

11. Versatile Visible-Light-Driven Synthesis of Asymmetrical Phosphines and Phosphonium Salts.

Author

Arockiam PB, Lennert U, Graf C, Rothfelder R, Scott DJ, Fischer TG, Zeitler K, and Wolf R

Abstract

Asymmetrically substituted tertiary phosphines and quaternary phosphonium salts are used extensively in applications throughout industry and academia. Despite their significance, classical methods to synthesize such compounds often demand either harsh reaction conditions, prefunctionalization of starting materials, highly sensitive organometallic reagents, or expensive transition-metal catalysts. Mild, practical methods thus remain elusive, despite being of great current interest. Herein, we describe a visible-light-driven method to form these products from secondary and primary phosphines. Using an inexpensive organic photocatalyst and blue-light irradiation, arylphosphines can be both alkylated and arylated using commercially available organohalides. In addition, the same organocatalyst can be used to transform white phosphorus (P 4 ) directly into symmetrical aryl phosphines and phosphonium salts in a single reaction step, which has previously only been possible using precious metal catalysis., (2020 The Authors. Published by Wiley-VCH GmbH.)

Published
2020
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results