Tuning Rotation of Anisotropic Particles in a Uniform Magnetic Field

The assembly of field-responsive anisotropic particles into targeted macrostructures requires judicious particle design. H-shaped particles are an intriguing class of shapes to study since they should give rise to branched networks. As a first step towards understanding self-assembly of these particles, here we study the rotation of non-Brownian H-shaped particles. We develop a Finite Element Integration (FEI) method to identify the preferred particle orientation (relative to the applied field) at different values of the geometric parameters for an H shape and construct a phase diagram to generalize the results. We validate the theoretical predictions by comparing with experiments performed using magnetic hydrogels synthesized using stop-flow lithography. The results obtained in this work will aid in selecting H-shaped particles for further self-assembly studies.