Tracking rotational diffusion of colloidal clusters.

  title={Tracking rotational diffusion of colloidal clusters.},
  author={Gary L Hunter and Kazem V Edmond and Mark T. Elsesser and Eric R. Weeks},
  journal={Optics express},
  volume={19 18},
We describe a novel method of tracking the rotational motion of clusters of colloidal particles. Our method utilizes rigid body transformations to determine the rotations of a cluster and extends conventional proven particle tracking techniques in a simple way, thus facilitating the study of rotational dynamics in systems containing or composed of colloidal clusters. We test our method by measuring dynamical properties of simulated Brownian clusters under conditions relevant to microscopy… 

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