ABSTRACT
While there are many methods available to determine the local motion of molecules in solid materials, ion beam analysis is perhaps uniquely well suited to measure the center of mass diffusion over longer ranges. Characterizing longrange diffusion is important since it enables us to understand processes such as drug release and delivery (Smith, Massingham, & Clough 2002), barrier properties (Clough et al. 2006), and absorption (Gall, Lasky, & Kramer 1990).
