Crystal organic single

Morphology Changes of Organic Crystals by Single-Crystal-to-Single-Crystal Photocyclization 527... 

TCNQ-Polyphosphazene Systems. Tetracyanoquinodimethane (XX) salts crystallize in the form of stacked arrays that allow electrical semiconductivity (42). Although this phenomenon has been studied in many laboratories, it has not been possible to fabricate conductive films or wires from these substances because of the brittleness that is characteristic of organic single crystals. However, it seemed possible that, if the flexibility and ease of fabrication of many polyphosphazenes could be combined with the electrical properties of TCNQ, conducting polymers might be accessible. 

K. Kemnitz, N. Tamai, I. Yamazaki, N. Nakashima, and K. Yoshihara, Site-dependent fluorescence 1 ifetimes of isolated dye molecules adsorbed on organic single crystals and other substrates, J. Phys. Chem. 91, 1423-1430(1987). 

Single crystal-to-single crystal reactions are quite rare in solid-state organic photochemistry, and we were fortunate to discover a second example in the Yang photocyclization of the 1-phenylethylamine salt of 2-methyl-2-benzoyl-p-carboxylic acid 39 [37]. 

Mas-Torrent M, Durkut M, Fladley P, Ribas X, Rovira C (2004) High mobility of dithiophene-tetrathiafulvalene single-crystal organic field effect transistors. J Am Chem Soc 126 984-985... 

The examples of ex situ steady-state X-ray photodiffraction utihzed to follow the photodimerizations of olefin bonds in a single-crystal-to-single-crystal (or nearly so) manner are ubiquitous in the chemical literature. The interest of sohd-state chemists in this reaction dates back to the work of Cohen and Schmidt [30, 31], and it has become much of a guinea pig in organic solid-state photochemistry. In 1993, Enkelmann and collaborators published two seminal papers in the Journal of the American Chemical Society [32] and in Angewandte Chemie [33], where they presented a series of structures of a-tra s-cinnamic acid crystals reacted to various extents. These reports laid the way for a plethora of later studies on the olefin photodimerization reaction. The convenience of the high conversion and the simple mechanism, combined with the relatively small structural perturbation that it requires, has turned this reaction into a very useful tool to probe intermolecular... 

The organic single crystals considered here for hole injection are composed of aromatic molecules with the following structural formulas ... 

Kommandeur, J. Photoconductivity in organic single crystals. J. Phys. Chem. Solids 22, 339 (1961). 

Fig. It. Schematic diagram illustrating ilie ability of nonlinear maierials lo dmible ilie frequency of incident laser radiaiion and also function as a paramedic amplifier when two beams of different frequency are involved. Most nr the non-cetttnosymmeiric solids currently in use are inorganic, hui ihey may be replaced by organic single crystal ihin films...

Olovsson, G., Scheffer, J. R., and Trotter, J. (1997) Determination of the Absolute Steric Course of an Enantioselective Single Crystal-to-Single Crystal Photorearrangement, J. Am. Chem. Soc., 119, 1462-1463,. (e) Leibovitch, M., Olovsson, G., Scheffer, J. R., and Trotter, J. (1997) Absolute configuration correlation studies in solid state organic photochemistry, PureAppl. Chem., 69, 815-823. 

The triplet-triplet interaction, postulated to explain increased quantum yield of thin film organic LEDs, has been well known in EF of organic single crystals [2,21,41], One of the most spectacular manifestation of this type excitonic interactions is spatial distribution of EL emission (see Sec. 3.3). Interestingly, the EL light output resulting from the free-trapped carrier recombination (Oel) with respect to that underlain by free carriers recombination (Oel) does not depend on the trap depth [2]... 

Figure 96 Temperature dependence of the charge carrier mobility in organic single crystals, (a) The electron mobility in a crystal grown from moderately purified perylene (see Ref. 28), and (b) the electron (/ ) and hole (// ) mobilities in synthetic ultrapurified anthracene crystals at an electric field E 2.3x10 V/cm directed along the crystallographic axes b (adapted from Ref. 436a).

Similar single crystal-to-single crystal reactions of organic compounds have been reported [25-30]. 

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