Demonstration of the Elusive Concentration-Gradient Paramagnetic Force

Using classical electrochemistry, it is demonstrated that the concentration-gradient paramagnetic force, F_∇C, is a body force proportional to |B|² acting parallel to the concentration gradient of electrogenerated radicals. F_∇C can balance gravity, holding volumes of solution wherein mass transfer continues to take place by diffusion. In contrast to usual levitation forces, F_∇C does not depend on field gradients and may be present even in homogeneous magnetic fields. Understanding the properties of F_∇C is relevant to magnetic confinement and levitation and is speculated even to propulsion with objects having permanent susceptibility gradients.