Fig. 7.7 Perspective view of the stagnation graph of the current density vector field in planar
ethene C 2 H 4 , with magnetic symmetry D 2h ðC 2h Þ. The uniform external magnetic field B is applied
in the direction of the C–C bond, coincident with the z axis. Here and in the following figures,
green (red) lines denote diamagnetic (paramagnetic) vortices, saddle lines are blue
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ethene C 2 H 4 , with magnetic symmetry D 2h ðC 2h Þ. The uniform external magnetic field B is applied
in the direction of the C–C bond, coincident with the z axis. Here and in the following figures,
green (red) lines denote diamagnetic (paramagnetic) vortices, saddle lines are blue
7 Topology of Quantum Mechanical Current Density …
181