Sheets and rational synthesis are not like fire and water! Hexafunctional terpyridine monomers can be laterally connected by metal salts to result in a mechanically stable, sheetlike entity that can be transferred from the air/water interface to a solid substrate (see the folded, ca. 1.4 nm thin film) and spanned over micrometer‐sized holes. This result is considered an important step on the way to 2D polymers.
We demonstrate a novel electronic readout for quadrant photodiode based optical beam deflection setups. In our readout, the signals used to calculate the deflections remain as currents, instead of undergoing an immediate conversion to voltages. Bipolar current mirrors are used to perform all mathematical operations at the transistor level, including the signal normalizing division. This method has numerous advantages, leading to significantly simpler designs that avoid large voltage swings and parasitic capacitances. The bandwidth of our readout is solely limited by the capacitance of the quadrant photodiode junctions, making the effective bandwidth a function of the intensity of photocurrents and thus the applied power of the beam deflection laser. Using commercially available components and laser intensities of 1-4 mW we achieved a 3 dB bandwidth of 20 MHz with deflection sensitivities of up to 0.5-1 V/nm and deflection noise levels below 4.5 fm/Hz. Atomic resolution imaging of muscovite mica using FM-AFM in water demonstrates the sensitivity of this novel readout.
New macrocyclic amphiphiles with two or three integrated 1,8-anthrylenes have been synthesized by an iterative Sonogashira cross-coupling protocol. The final cyclization has been conducted with 80% yield under cuprous-free dilution conditions. Formation of a monolayer at the air/water interface has also been demonstrated. These results open the intriguing possibility to construct large 2D supramolecular/macromolecular systems for which unique photophysical and -chemical properties are expected.
Hexafunktionelle Terpyridinmonomere können lateral durch Metallsalze verbunden werden, was zu einem mechanisch stabilen, blattähnlichen Gebilde führt, das von der Luft‐Wasser‐Grenzfläche auf einen festen Träger überführt (siehe den gefalteten, ca. 1.4 nm dünnen Film) und über μm‐große Löcher gespannt werden kann. Dieser Befund ist ein wichtiger Schritt auf dem Weg hin zu zweidimensionalen Polymeren.
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