Intrachain NOEs

In this compound, no intrachain D+A short contacts were found and the closest interatomic separation between the anion and the Cp ring corresponds to Ni... C contacts (cl) exceeding the sum of the van der waals radii, dw, by 11 %. In this salt the closest interchain arrangements are similar and present an out-of-registry disposition (pairs I—II and I-IV). This arrangement is shown in Fig. 8b. The closer interchain contacts (d2) involve C atoms from the Me groups of the cations and S atoms of the anions, with a separation exceeding dw by 8%. 

Fe(Cp )2]2[Cu(mnt)2]. In this compound both cations from the D+D+ pair in the repeat unit are perpendicular to the chain direction as shown in Fig. 26b. Short intrachain contacts were observed and involve the Cu from the anion and a C from one of the Me groups in the cation, with a Cu-C distance of 3.562 A. The side-by-side cations are relatively separated and the closer C-C separations exceeds intrachain contacts were observed and the chains are essentially isolated. 

This enzyme (RNase A) is a single chain protein of 124 amino acid residues, cross-linked by four intrachain disulfide bonds. Limited proteolysis of the enzyme cuts a single peptide bond between residues 20 and 21 (Richards and Vithayathil, 1959). The derived protein, RNase S, retains enzymic activity although the N-terminal peptide of 20 amino acids (S-peptide) is no longer covalently attached to the balance of the molecule (S-protein). Removal of S-peptide from... 

A representative example for the information extracted from a TRMC experiment is the work of Prins et al. [141] on the electron and hole dynamics on isolated chains of solution-processable poly(thienylenevinylene) (PTV) derivatives in dilute solution. The mobility of both electrons and holes as well as the kinetics of their bimolecular recombination have been monitored by a 34-GHz microwave field. It was found that at room temperature both electrons and holes have high intrachain mobilities of fi = 0.23 0.04 cm A s and = 0.38 0.02 cm / V s V The electrons become trapped at defects or impurities within 4 ps while no trapping was observed for holes. The essential results are (1) that the trap-free mobilities of electrons and holes are comparable and (2) that the intra-chain hole mobility in PTV is about three orders of magnitude larger than the macroscopic hole mobility measured in PTV devices [142]. This proves that the mobilities inferred from ToF and FET experiments are limited by inter-chain hopping, in addition to possible trapping events. It also confirms the notion that there is no reason why electron and hole mobilities should be principally different. The fact... 

A 3(— 1.143) helical conformation was proposed. A complete determination of the unit-cell dimensions and the lateral arrangement of the chains was not possible, due to the paucity of the X-ray data. Two intrachain hydrogen-bonds, of the type OH-2-(/3-D-Galp)—0-5-(a-D-Manp) and OH-2-(a-D-GalpA)—0-3-(a-D-Manp), were proposed. No intrachain hydrogen-bond is possible with the a-D-Manp side-group. 

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