Special Topic 3.2 Organic light-emitting diodes OLEDs

Special Topic 3.2 Organic Light-Emitting Diodes (OLEDs) 

Organized and constrained media may provide cavities and surfaces, sometimes called microreactors or nanoreactors,171 that can control the selectivity of photochemical reactions of reactants. There are many types of microreactors, for example, molecular aggregates of micelles or monolayers, macrocyclic host cavities of crown ethers or cyclodextrins and microporous solid cavities and/or surfaces of zeolites, silica or 

UV VIS absorption spectra are called electronic spectra, because the observed absorption bands indicate the frequencies of the electromagnetic radiation at which the energy of a photon, hv, matches the energy difference between the electronic ground state and an electronically excited state of the absorbing molecules, AE = hv. The absorption and emission spectra (Section 3.4) of a substrate should be determined at the outset of any 

The non-SI unit cm 1 (1 im 1 = 104cm J) is mostly used in IR, Raman and microwave spectroscopy. In this text, absorption spectra are shown on a wavenumber scale A(v), v = vjc = 1/2, [v] = im, mnning from right to left, so that the wavelengths, shown on top of the diagrams on a nonlinear scale, still increase to the right as is more customary to the chemist. To convert to a molecular energy scale we use the relation E = N. hc v to obtain the practical Equation 3.1. 

For the determination of molar absorption coefficients, s, care must be taken to use clean glassware and solvents and the instrumental baseline must be recorded or calibrated prior to measurement. Absorbance measurements are most accurate in the range 0.1 A 1.5 lower absorbances are prone to baseline errors and those exceeding 1.5 should be avoided, because the amount of light passing the sample cell becomes very small and the readings are 

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