Magnetic field circulating charges

Cyclotron frequency. In a magnetic field, a charged particle moving with speed m in a plane perpendicular to the magnetic flux density B is forced to perform a circular motion (For a more general treatment, see Sect. 50.3.3.1). The angular frequency of this circulation is the cyclotron frequency. For electrons, the cyclotron frequency is... 

The curl of the circulating A is a magnetic field B, by identity (3). There may, of course, be present additional A potential that has zero curl, but that additional longitudinal AL potential or AL current does not produce a magnetic field per se. However, its change dA/dt does interact with charges as an E-field. 

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... 

Magnetic moment A vector quantity expressed in units of angular momentum that relates the torque felt by the particle to the magnitude and direction of an externally applied magnetic field. The magnetic field associated with a circulating charge. 

Owing to different localization properties of the orbitals in the other cu-mulenes this last statement is no longer valid for all the cumulenes under consideration. Evidently, the circulating charge densities associated with the wpf and transitions in allenes induce a magnetic field in the x direction. 

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