  Taking into account the structural transition and long-range interaction
(lattice effect), we resort to the Ewald-Kornfeld formulation and developed
Maxwell-Garnett theory for uniaxially anisotropic suspensions to calculate the
effective permeability of inverse ferrofluids. And we also consider the effect
of volume fraction to the magnetophoretic force on the nonmagnetic spherical
particles submerged in ferrofluids in the presence of nonuniform magnetic
field. We find that the coupling of ac and dc field case can lead to
fundamental and third harmonic response in the effective magnetophoresis and
changing the aspect ratio in both prolate and oblate particles can alter the
harmonic and nonharmonic response and cause the magnetophoretic force vanish.
