Investigation Of Organic Molecules Research Articles

Versatile electrochemiluminescent organic emitters

Organic luminophores for electrochemiluminescence (ECL), namely polycyclic aromatic hydrocarbons, have been the first molecules investigated since the beginning of ECL studies. Moving from organic solvents to water-based solutions in view of analytical applications, the attention on ECL emitters shifted to soluble inorganic complexes, which prevailed in both fundamental and applied research. However, the investigation of organic molecules has recently revived owing to new synthetic procedures and concepts. Polymeric nanoparticles, surface functionalisation, aggregation-induced emission (AIE), and thermally activated delayed fluorescence (TADF) sparked the research with renovated interest for organic molecules. Here, we introduce and summarise these new concepts behind organic emitters for ECL.

Investigations of Organic Molecules Using Entangled Photons as a Novel Spectroscopic Tool

Investigations of Organic Molecules Using Entangled Photons as a Novel Spectroscopic Tool

(Invited) Evaluation of Tailored Organic Molecules for Cathode Passivation in High Voltage Lithium-Ion Batteries

Redox-active organic compounds have been explored as electrolyte additives for lithium-ion batteries, for purposes ranging from mitigation of excess current in overcharging cells to passivation of electrode surfaces to stabilize surfaces that would otherwise lead to electrolyte decomposition. Especially when expanding the voltage range in charging of lithium-ion cells, passivation becomes more critical to cell longevity during operation. Electrolyte additives containing purposefully weak covalent bonds have been employed in high-voltage (e.g. NMC cathodes) lithium-ion cells, which are tailored to react with hydrofluoric acid – a product of decomposition of fluorine-containing anions present in the electrolyte. Here we report results from the investigation of organic molecules as electrolyte additives with functionality aimed to react with/at cathode surfaces to form passivating films. These organic molecules with varying oxidation potentials (3.4 V vs. Li+/0 and above) house main group ad-atoms unique from those contained in the electrode, binder, conductive fillers, and electrolyte solutions. This allows for surface imaging and electrolyte analysis to determine the location and reaction of such additives following formation cycling.

High pressure studies of the organic triplet

Abstract High pressure up to 50 kbar generated in a diamond anvil cell has been applied to the investigation of organic molecules in their phosphorescent triplet state. Experimental techniques include specifically adapted optically detected magnetic resonance (Odmr) and optical spectroscopy. This paper reviews some of the high points of our results. On the microscopic scale there is no isotropic compression. Pressure enhances the interaction of a chromophore with its neighbours in a few specific modes according to crystalline packing. These interactions may shift the energy levels of the chromophore, or enhance the dynamical processes in the crystal. A variety of pressure-induced effects may be rationalized on this basis.

On the electronic structure of barrelene-based rigid organic donor-acceptor systems. AnINDO model study including solvent effects

We present an INDO/S molecular-orbital investigation of organic molecules containing a barrelene moiety that provides a rigid link between an aromatic donor and a maleic ester acceptor group. Molecules of this type have recently been synthesized and characterized spectroscopically. We discuss the ground state and various excited states both in vacuo and in solution. Solvent effects are incorporated by use of an electrostatic cavity model which is not restricted to a spherical cavity, but allows for a cavity shape that is adapted to the solute molecule. The calculations indicate low-lying charge-transfer (CT) excitations in the region of the first aromatic transitions, even in the gas phase. © 1992 John Wiley & Sons, Inc.