Supramolecular Assembly of Pyrene-DNA Conjugates into Columnar Vesicles

This poster describes the supramolecular assembly of DNA conjugates functionalized with pyrene sticky-ends. After hybridization, the 3’-end modified DNA single strands self-assembled into vesicles with diameters of 50–200 nm. Columnar packed aggregated and multilamellar vesicles were observed by cryo-EM

Self-Assembled Molecular-Electronic Films Controlled by Room Temperature Quantum Interference

If single-molecule, room-temperature, quantum interference (QI) effects could be translated into massively parallel arrays of molecules located between planar electrodes, QI-controlled molecular transistors would become available as building blocks for future electronic devices. Here, we demonstrate unequivocal signatures of room-temperature QI in vertical tunneling transistors, formed from self-assembled monolayers (SAMs), with stable room-temperature switching operations. As a result of constructive QI effects, the conductances of the junctions formed from anthanthrene-based molecules with two different connectivities differ by a factor of 34, which can further increase to 173 by controlling the molecule-electrode interface with different terminal groups. Field-effect control is achieved using an ionic liquid gate, whose strong vertical electric field penetrates through the graphene layer and tunes the energy levels of the SAMs. The resulting room-temperature on-off current ratio of the lowest-conductance SAMs can reach up to 306, about one order of magnitude higher than that of the highest-conductance SAMs

OpenFermion: The Electronic Structure Package for Quantum Computers

Quantum simulation of chemistry and materials is predicted to be an important application for both near-term and fault-tolerant quantum devices. However, at present, developing and studying algorithms for these problems can be difficult due to the prohibitive amount of domain knowledge required in both the area of chemistry and quantum algorithms. To help bridge this gap and open the field to more researchers, we have developed the OpenFermion software package (www.openfermion.org). OpenFermion is an open-source software library written largely in Python under an Apache 2.0 license, aimed at enabling the simulation of fermionic models and quantum chemistry problems on quantum hardware. Beginning with an interface to common electronic structure packages, it simplifies the translation between a molecular specification and a quantum circuit for solving or studying the electronic structure problem on a quantum computer, minimizing the amount of domain expertise required to enter the field. The package is designed to be extensible and robust, maintaining high software standards in documentation and testing. This release paper outlines the key motivations behind design choices in OpenFermion and discusses some basic OpenFermion functionality which we believe will aid the community in the development of better quantum algorithms and tools for this exciting area of research.Comment: 22 page

The evolution of disaster early warning systems in the TRIDEC project

The TRIDEC project (Collaborative, Complex, and Critical Decision Processes in Evolving Crises) focuses on real-time intelligent information management in the Earth management domain and its long-term applications. It is funded under the European Union’s seventh Framework Programme (FP7). The TRIDEC software framework is applied in two application environments, which include industrial subsurface drilling (ISD) and natural crisis management (NCM). For each domain, three consecutive demonstrators with extended capabilities are developed and field-tested during the projects lifespan. This article focuses on the technical advances achieved by the light-, mid- and heavyweight NCM demonstrators for Tsunami Early Warning

Supramolecular Assembly of Pyrene-DNA Conjugates into Vesicles

Over the last two decades, supramolecular polymers have been successfully used for the assembly of organized molecular arrays. Complementary DNA strands create a defined arrangement upon hybridizing and the obtained DNA framework can be exploited for the introduction of modifications at spatially controlled places of the supramolecular assemblies. In previous work, assemblies containing DNA were decorated with sticky ends containing polyaromatic hydrocarbons (PAH). Our group observed light-harvesting properties in supramolecular vesicles assembled from phenanthrene-DNA conjugates.[1] In addition, aggregation-induced emission (AIE) type chromophores were introduced as sticky ends forming AIE-active supramolecular assemblies using E-tetraphenylethylenes instead of phenanthrene.[2] In this work, 2,7-pyrene (Figure 1A), 1,6-pyrene, and 1,8-pyrene was investigated as stick end modification to DNA. AFM studies of 2,7-pyrene reveal the self-assembly of the conjugates into spherical objects (Figure 1B). Similar results were obtained for DNA-conjugates of the 1,6-pyrene and 1,8-pyrene isomers. In addition to AFM studies, fluorescence and UV-vis spectroscopy will be presented and discussed

Synthesis and Characterisation of Metallo-Porphyrin Dyads

In comparison to other chromophores, porphyrins show very distinct photophysical and electrochemical features. Their redox and optical properties can easily be tuned by substitutions on the central porphyrin core, as well as by the insertion of a different metal ion in the cavity.[1–3] In this work, we have prepared four different dyads (Figure 1), where two metalloporphyrin units are connected either directly or via a phenylene linker at their meso-positions. A discrepancy in electronic and Coulombic interactions between two porphyrin cores is unambiguously demonstrated by cyclic voltammetry, UV-Vis absorption and fluorescence emission spectra. All these results will be presented and discussed in the virtual poster video

A donor-acceptor ensemble: merging of TTF and dipyrrolylquinoxaline difluoroborate chemistry

Tetrathiafulvalene(TTF)-fused donor-acceptor (D–A) ensembles are of high interest due to their unique (opto)electronic properties and potential applications in organic conductors, photovoltaics, sensors, switches and molecular electronics. A direct annulation of a TTF with a variety of electron-acceptors has been achieved for studying photo-induced intramolecular charge transfer (ICT) as well as the photogeneration of long-lived charge separated states in resultant D-A systems. Herein, we describe redox and optical properties of a new D–A ensemble (Chart 1) which was prepared by complexation of BF2 with a TTF-fused 2,3-di(1H-2-pyrrolyl)quinoxaline ligand. A detailed experimental and theoretical study of an ICT process in TTF-QB is presented

From GITEWS to InaTEWS: An Architectural Blue Print

After the Sumatra earth quake in December 2004 the Federal Republic of Germany supports with the GITEWS project the Indonesian government to establish the nucleus of a national tsunami early warning system for the Indian Ocean. In the context of GITEWS dedicated sensors like buoys with underwater pressure sensors, tide gauge sensors, GPS sensors and seis-mometers are developed and deployed. On the basis of the data provided by the GITEWS sensors a simulation system predicts the creation and propaga-tion of a tsunami wave and enables the staff of the warning centre in Jakarta to issue precise warning messages for the affected costal areas. However, Indonesia has coast lines not only with the Indian Ocean but with the Pacific Ocean too and there are data from non-GITEWS sensors which must be in-cluded to improve the warning process. Therefore, the concepts developed during the GITEWS project have to be extended to incorporate additional sensor data as well as the whole Indonesian coast line into the scope of the warning system to reach the ultimate goal: The development of an Indone-sian Tsunami Early Warning System (InaTEWS). The purpose of this paper is to develop an architectural blue print for InaTEWS. It is divided as follows. As an introduction, section 2 gives a short description of the architecture realized in the GITEWS project. Section 3 deals with the distributed data sources and responsibilities in Indonesia and discusses patterns to consolidate data for InaTEWS whereas section 4 de-velops the architectural blue print for the realization of InaTEWS