Organic salts charge transfer

Al) charge-transfer salts (organic conductors and superconductors) [8] ... 

Charge-Transfer Salts. Most charge-transfer salts can be prepared by direct mixing of donors and acceptors in solution. Semiconducting salts of TCNQ have been prepared with a variety of both organic and inorganic counterions. Simple salts of the type TCNQ can be obtained by direct reaction of a metal such as copper or silver with TCNQ in solution. Solutions of metal iodides can be used in place of the metals, and precipitation of the TCNQ salt occur direcdy (24). 

Since the discovery of the first organic conductors based on TTF, [TTF]C1 in 1972 [38] and TTF - TCNQ in 1973 [39], TTF has been the elementary building block of hundreds of conducting salts [40] (1) charge-transfer salts if an electron acceptor such as TCNQ is used, and (2) cation radical salts when an innocent anion is introduced by electrocrystallization [41]. In both cases, a mixed-valence state of the TTF is required to allow for a metallic conductivity (Scheme 5), as the fully oxidized salts of TTF+ cation radicals most often either behave as Mott insulators (weakly interacting spins) or associate into... 

X-ray crystallographic analysis of the crystalline [bicumene, NO+] charge-transfer salt confirms that the charge-transfer color arises from a close approach of NO+ to the centroid of the phenyl moiety (see Fig. 10) with a non-bonded contact to an aromatic carbon of 2.63 A.194 The orange solution of bicumene bleaches slowly over a long period in a thermal reaction at room temperature (in the dark) or rapidly via irradiation of the CT band at low temperature. In both cases, l,l,3-trimethyl-3-phenylindane is obtained as the principal organic product (equation 63). 

Chemical research of molecular metals was activated by the discovery of the metallic charge transfer salt TTF-TCNQ in 1973 [40]. Two basic molecular architectures have been studied intensively. One is based on organic molecules with the... 

Ashizawa M, Kimura S, Mori T, Misaki Y, Tanaka K (2004) Tris-fused tetrathiafulvalenes (TTF) highly conducting single-component organics and metallic charge-transfer salt. Synth Met 141 307-313... 

Mori T, Terasaki I, Mori FI (2007) New aspects of nonlinear conductivity in organic charge-transfer salts. J Mater Chem 17 4343 347... 

A New Approach to High-Resolution Lithography Based on Conducting Organic Charge Transfer Salts... 

Since the discovery in 1973 of metal-like conductivity in the charge transfer salt tetrathiafulvalene-tetracyano-p-quinodimethane (TTF-TCNQ, 1,-2), a host of new materials have been prepared displaying this interesting property. Widespread research on these materials has led to an improved understanding of the physics underlying the organic metallic state, and to a succession of molecular modifications which have enhanced these properties. ... 

Perhaps the two most fundamental requirements for high conductivity in organic charge transfer salts are ... 

At this stage, the potential of E-beam induced reverse electron transfer in conducting organic charge transfer salts for lithographic applications is unclear. However, these materials do possess a rather unique combination of properties that may be of considerable value in future applications where traditional resist materials may be unsuitable. Some of the key features of these new resists are summarized below ... 

Gerald A. Segal, Semiempirical Methods of Electronic Structure Calculation, Pt. A Techniques, in Modern Theoretical Chemistry, Vol. 7, Plenum, New York, 1977. Mark A. Ratner, John R. Sabin, and Samuel B. Trickey, Applications of Model Hamiltonians to the Electron Dynamics of Organic Charge Transfer Salts in Uncertainty Princ. Found. Quantum Mech., William Charles Price and Seymour S. Chissick, Eds., Wiley, Chichester, 1977. 

Neutral - ionic transition in organic charge - transfer salts... 

Although most compounds prepared from neutral parent molecules are neutral DA complexes, in some cases an ionic charge-transfer salt results. In addition, there are compounds prepared from D+p and A-q subunits which have been found to be ionic. Many of the ionic crystals involve A q units that are variants on metal bis-ethylene-1,2-dithiolenes, namely [M(tfd)2] and [M(mnt)2]-2. A variety of planar organic cations have been used to prepare such solids TTF+ M5), POZ+ 56 57), PTZ+ 56 57), and NMP+ 59). A... 

This chapter deals with 1,3-dithiole compounds such as 1,3-dithiolylium ions (1), mesoionic l,3-dithiol-4-ones (2), 1,3-dithioles (3), 1,3-dithiolanes (4) and the tetrathiaful-valene system (5). During the last 15 years the chemistry of 1,3-dithiole compounds has developed considerably. One reason is that tetrathiafulvalene and its derivatives serve as donors in organic charge-transfer salts which exhibit the electrical properties of quasi-one-dimensional metals. For the preparation of such organic metals, 1,3-dithiolylium cations serve as useful synthetic intermediates. 

Nalwa HS, "Handbook of Organic Conductive Molecules and Polymers", Vol. 1, "Charge-Transfer Salts, Fullerenes and Photoconductors" Vol. 2, "Conductive Polymers Synthesis and Electrical Properties" Vol. 3, "Conductive Polymers Spectroscopy, Photo-Physics and Applications" Vol. 4, "Conductive Polymers Transport and Physical Properties", Wiley, Chichester, 1997. 

The paper is organized as follows. Sect. 2 describes the general principles and recent results for the synthesis of cyclotriveratrylenes Sect. 3 describes some applications of these compounds to host-guest chemistry. This latter section is devoted principally to the cryptophanes, and to host molecules containing one CTV unit that have recently been described. Sec. 4 presents some prospective work in the field of material sciences, i.e., ferroelectric liquid crystals and organic three-dimensional charge transfer salts. 

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