Bridge geometry

Au atom (see Fig. 15b). The high conductance values H represent an all-trans alkyl chain in combination with both sulfurs coordinated to two Au atoms in a bridge geometry (Fig. 15c). The theoretically predicted fourfold increase of the conductance, as compared to an atop-atop all-trans bridge, is close to the experimentally observed increase by a factor of 5. Other possible configurations with all-trans conformations (e.g., atop-bridge, multiple molecular junctions) are assumed to contribute as part of the distribution to the less-dominant peaks in the conductance histograms (e.g., M2, H2, and H3 in Fig. 13). 

In the course of our investigations for improved single-source precursors for the spray CVD of CIGSSe chalcopyrite thin films, we have continued to expand the molecular design of SSPs based on the [ ER3 2Cu(p-QR )2M(QR )2 ] (Q = S, Se E = P, As, Sb) architecture (hereafter the symbol p, which indicates a bridging geometry, will be eliminated for the sake of simplicity and clarity).38... 

Finally, addition of azide to methemocyanln. Figure 5 (Bottom), yields a charge transfer spectrum which shows an Ap B. pattern very similar to the spectrum of the y-1,3 azide model complexes. Thus azide binds In an analogous y-1,3 bridging geometry to the binuclear site In methemocyanln. 

Experimental investigations have been supported and stimulated by theoretical calculations giving comparative data for the whole series from lithium to cesium. For example, ab initio studies of the allyl derivatives MC3H5 (M = Li, Na, K, Rb, or Cs) show that symmetrically bridged geometries are... 

Table J List of the studied clusters, classified by the type of surface passivation (rows) and by the core size (columns). Full-H stands for a passivation by H atoms only Si-O-Si by H atoms plus O in the bridge geometry Si=0 by H atoms plus O in the double-bond geometry and Si-O-Si + Si=0 by H atoms plus O both in the bridge- and double-bond geometry...

However, when a linear geometry cannot be achieved, as in the case of the cyclohexenyl cation 167, a bridged geometry of type 168 (in a nonclassical formulation) may become more stable, at least when R = Alkyl. This type of bridged ion is likely to be generated in the triple... 

Bridged cations have been indicated as intermediates of the addition of bromine to dialkylacetylenes on the basis of the exclusive trans mode of the reactions. Bridged cations are in each case likely to be formed in the addition of sulphenyl derivatives to alkyl- as well as to arylacetylenes. The retention of trans configuration and the anchimeric assistance effects observed in SNl-type reactions of j8-arylthiovinyl sulphonates indicate that the bridged geometry is always favoured over a linear one. 

The most important two-electron bonding interactions that take place are between two of the acetylene x orbitals, ira and it (see 136), and the d band. ir and w point toward the surface, have greater overlap with metal overlaps, and they interact preferentially with different parts of the band, picking out those metal surface orbitals with nodal patterns similar to that of the adsorbate. 137 shows this in the parallel bridging geometry at hand the ra orbital interacts better with the bottom of the surface z2 band and the r with the top of that band. 

Fig. 35. Diagrammatic explanation of the transition dipole vector coupling treatment for two possible peroxide bridging geometries, /<-dioxo and ft-monooxo, and comparison to oxyhemocyanin (see text for explanation)...

Addition of SO2 to an oxygen-free solution of Pd2(dppm)2Cl2 (dppm = Ph2PCH2PPh2) in CH2CI2 results in the formation of the insertion product with an A-frame bridging geometry". 

There are very specific changes of the hydrogen bridge geometry in the cations of 2,7-disubstituted proton sponges. The measurements of such systems were performed for five salts with cations 44 H+, 101-II1,102 H+, 105 H+ and 112 H+. The ortfio-substituents in these cations display a distinct steric pressure on the adjacent A-methyl groups, pushing... 

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