Charge circulation

Unsaturation is normaly expressed meq/g but it is convenient to convert it to hydroxyl units for charge circulation. 

The special properties of aromatic compounds and conjugated systems are related to the regular alternation of single and second-order C-C bonds along molecular chains. Each second order bond is associated with a balanced charge circulation and a couple of odd electrons with paired spins. The... 

The radius of charge circulation follows Figure 6.5 Tub-like structure c ° from ... 

The molecular structures and charge circulation circles for ethylene and benzene are compared to scale in Figure 6.6(a). In both cases the match is close enough to conclude that the circles pass through the hydrogen positions. 

Nuclear Magnetic Resonance Many textbooks mention charge circulation, inferred from NMR measurements in a magnetic field, applied perpendicular to aromatic planes, as evidence for the delocalization of pz electrons. The only mechanism whereby such a ring current can be induced is by... 

The radius of charge circulation in the twisted molecule is not specified but should be of the order of the C—C bond length. In fact, using r = 117 pm, the calculated energy of 270 kJmol-1 agrees with the accepted 7r-bond strength in ethylene. 

NMR signal (compare the 6" Sn values of 5 and 8). Thus, paramagnetic effects as the result of Bo induced charge circulation involving the formally unoccupied Sn-pz orbital arises mainly from Sn-C or Sn-N bonds and to a minor extent from the lone pair of electrons at the tin atom. This explains that the dimerization of stannylenes causes a marked increase in Sn nuclear shielding since the Sn-p orbital is now used in donor-acceptor interaction. ... 

I) Isolated singularities that must be of the (3, 1)-type (see Figure 9) and are associated with separa-trices that are toplological spheres. A separatrix is a surface of zero flux when this is a topological sphere (i.e., a closed surface that may be continually deformed into a sphere), it defines a region of space where charge circulation may occur but outside of... 

Figure 12. Stagnation graph (a) and the charge circulation (b) for a closed-shell atom under an external magnetic-field. The graph is a straight vortical line through the nucleus, the axis of Larmor rotation of the charge under the magnetic field.

The electrodes are bipolar and are typically composed of carbon plastic. The presence of bromine precludes the use of metal electrodes—even titanium can corrode in this environment. A high-surface-area carbon layer is added to the positive side of the electrode to increase the area for reaction. On charge, circulation of the electrolyte removes the com-plexed polybromide as it is formed, and on discharge complexed polybromide is delivered to thee electrode surface. Circulation of the electrolyte also reduces the tendency for zinc dendrites to form and simplifies thermal management of the battery. Thermal management will be needed in many applications of present and advanced batteries. 

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