Abstract:

This talk is in the area of computational molecular simulation:
specifically, correlating geometric and mechanical properties of
materials using computational models.

The transport of molecules through carbon nanotubes and the effect of
filling on nanotube mechanical properties are examined with classical
molecular dynamics simulations.

In particular, the transport of molecular oxygen and small organic
molecules through nanotubes is examined as a function of tube diameter
and configuration.

Molecular transport mechanisms are predicted to depend on molecular
size and shape and nanotube diameter. The insights from these
simulations indicate how nanotube-based membranes might be tailored
for optimal performance.

In addition, the mechanical responses of filled nanotubes subjected to
applied bending, tensile, compressive, and torsion forces are examined
and compared to the responses of pristine systems.

The results indicate that the forces needed to deform filled nanotubes
are larger than those required to deform empty nanotubes. The
magnitude of the increase depends on the type of filling material and,
in the case of multi-walled tubes, the number of inner tubes. The
insights and failure criteria developed from these simulations can be
used to design carbon nanotube-based devices and materials, such as
nanoelectromechanical systems and nanocomposites, which undergo
loading through the external application of forces.