Semi-conductivity properties

Finally, stereoregularity of the initial PAN also affects the disposition of a CTC obtained from this polymer to the formation of photoinduced states with complete charge transfer. Both the values of the stationary concentration of these states and the rate of growth to this level, are considerably higher for a PCS obtained from the polymer with elevated stereoregularity. All this characterizes the effect of PCS stereoregularity on their reactivity in the formation of a CTC. The semi-conductive properties of PCS complexes of various classes with electron donors have been studied267, 268 ... 

The inherent metallic or semi-conducting properties of nanotubes are defined by the way the graphite sheets roll up during formation. Figure 10.7a shows the... 

Dipole development around a conductor immersed in an electrolyte with uneven oxidative properties is scale independent. Even tiny conductive or semi-conductive mineral grains in overburden will develop dipoles if there are redox differences across them. Almost all solids have some semi-conductive properties and therefore the nature of the conductive minerals is of less importance than the existence of a redox gradient. Large redox gradients in overburden contain polarisable minerals. 

This list can be divided into three main classes based mainly on function and redox state. First, applications that utilize the conjugated polymer in its neutral state are often based around their semi-conducting properties, as in electronic devices such as field effect transistors or as the active materials in electroluminescent devices. Secondly, the conducting forms of the polymers can be used for electron transport, electrostatic charge dissipation, and as EMI-shielding mate-... 

From the electronegativities shown in Figs. 2.4.2 and 2.4.3, it is seen that metals are less electronegative, with xs < 2, nonmetals are more electronegative, with xs > 2. Around xs 2, we have metalloid elements such as B, Si Ge, Sb, and Bi. Most of these elements have semi-conducting properties. For elements of the same group, xs decreases as we go down the Periodic Table. However, because of relativistic effects, for transition metals from group 7 to... 

Berg et al. 711 proposed that the adenine and cytosine residues in native DNA are reduced by a so-called electron hopping mechanism, the only condition for this being adsorption of protonated DNA at the electrode surface at the reduction potential of these bases. It was also assumed that the DNA is adsorbed in its A-form, exhibiting semi-conducting properties. There is consequently no surface denaturation of the DNA. 

The (semi)conductive properties of fullerene derivatives and carbon nanotubes have been a topics of intense recent interest. Unfortunately, at the time of writing it is still not possible to obtain well-defined samples of nano-tubes in sufficient amounts to carry out PR-TRMC measurements. Relatively pure, powder samples of C60 were however available in the mid-1990s and large, if short-lived, PR-TRMC transients could be observed. More recently attention has focused on the methyl ester of phenyl-C61-butyric acid (PCBM) which is a soluble C60 derivative that has found applications as the electron accepting component in hetero-junction materials for solar energy conversion. 

Impurity semi-conductors have assumed great importance in recent years, and have been extensively studied both on account of their semi-conducting properties and also on account of their applications as rectifiers and crystal triodes or transistors. 

At this point we seem to have come a long way from the chemistry of Joe Chatt. Is there really a connection between the stability of olefin complexes of platinum(ii) and the semi-conducting properties of GaAs In this short review I have tried to show that there is a direct relationship between the two. The class... 

BAND STRUCTURE CALCULATIONS AND (SEMI)CONDUCTING PROPERTIES (1978-TILL DATE)... 

The importance of the effect of vibrations on (hyper)polarizabilities has also become increasingly apparent since the mid-1990s. It is clear that vibrational effects are at crossroads between electronic and geometric effects and are also a manifestation of the electron-phonon interaction, which has already been shown to be of prime importance in estimating conducting and semi-conducting properties. 

The semi-conducting properties of conjugated polymers originate from the delocalized n orbitals formed in these carbon-containing compounds such as poly(phenylene vinylene), polythiophene and polyfparaphenylene). Like the OLED s described above, the polymer-OLED consists of a linninescent film, sandwiched between an anode and a cathode. 

The substance mixture in question, which causes the odor, undergoes an overall investigation by means of a sensor array. In doing so, the device makes use of the semi-conductive properties of various metal oxides, which are on the surface of 12 sensors which react to the gaseous substances which come in contact with them. The response also depends on the temperature, humidity and flow rate of the gas. Each sensor issues its own reply signal as soon as the sample of air touches its surface. 

Core-shell NPs exhibit unique properties with several possible applications. In the case of fluorescent saniconductor NPs, core-shell NPs help to increase the robustness and enhance the photoluminescence quantum yield as well as the probability of radioactive recombination. NPs with magnetic, plasmonic and semi-conducting properties can be used as cores or shells for manipulating the properties of these hybrid structures. Properties of either component within the hybrids (core-shell NPs) can be modulated through a conjugating component or interface. 

ABSTRACT. Bridged macrocyclic transition metal complexes using phthalo-cyanine and naphthalocyanine as macrocycles e.g. [PcML] with M = Fe, Ru Co and L = dib, tz, CN show good semi-conducting properties without external doping. The mechanism of the formation of the bridged macro-cyclic metal complexes is studied by H-NMR spectroscopy using the monomer PcFe(Me dib) . 

Phthalocyaninatoiron and ruthenium (PcFe, PcRu) as well as 2,3-naphthalocyaninatoiron (2,3-NcFe) form s-tetrazine bridged compounds e.g. [PcRu(tz)], which exhibit high semi-conducting properties without additional doping. Their conductivities are comparable to cyanide bridged metallomacrocycles [PcMCN]. ... 

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